Did adding the Feast of Sts. Mary, Martha and Lazarus clear up anything about the identity of Mary? I was just reading in the National Catholic Register that Sts. Mary Martha and Lazarus have been added to the church calendar by Pope Francis and that the reason they weren't on before was because of some sort of concern over whether Martha and Lazarus's sister Mary was the same as Mary Magdalene (seem unlikely if Magdalene means where she's from and these siblings were from Bethany).
The article doesn't address that concern, so I'm wondering if any new stuff has come to light or what Catholic scholars think is the relevance prohibiting having this 3-saint feast and a separate feast for St. Mary Magdalene.  Does Pope Francis just not think it's a stumbling block worth worrying about or do we know for sure that they're separate people?
Did adding the Feast of Sts. Mary, Martha and Lazarus clear up anything about the identity of Mary?
The answer seems to be no.
The decree of Pope Francis does not clear up the uncertainty. It simply adds these three saints together in the General Calendar of the Roman Rite.

Decree on the Celebration of Saints Martha, Mary and Lazarus in the General Roman Calendar
In the household of Bethany the Lord Jesus experienced the family spirit and friendship of Martha, Mary and Lazarus, and for this reason the Gospel of John states that he loved them. Martha generously offered him hospitality, Mary listened attentively to his words and Lazarus promptly emerged from the tomb at the command of the One who humiliated death.
The traditional uncertainty of the Latin Church about the identity of Mary - the Magdalene to whom Christ appeared after his resurrection, the sister of Martha, the sinner whose sins the Lord had forgiven - which resulted in the inclusion of Martha alone on 29 July in the Roman Calendar, has been resolved in recent studies and times, as attested by the current Roman Martyrology, which also commemorates Mary and Lazarus on that day. Moreover, in some particular calendars the three siblings are already celebrated together.
Therefore, the Supreme Pontiff Pope FRANCIS, considering the important evangelical witness they offered in welcoming the Lord Jesus into their home, in listening to him attentively, in believing that he is the resurrection and the life, and accepting the proposal of this Dicastery, has decreed that 29 July be designated in the General Roman Calendar as the Memorial of Saints Martha, Mary and Lazarus.
The Memorial must therefore appear under this title in all Calendars and Liturgical Books for the celebration of Mass and the Liturgy of the Hours; the variations and additions to be adopted in the liturgical texts, attached to the present decree, must be translated, approved and, after confirmation by this Dicastery, published by the Episcopal Conferences.
Anything to the contrary notwithstanding.
From the Congregation for Divine Worship and the Discipline of the Sacraments, 26 January 2021, Memorial of Saints Timothy and Titus, Bishops.

Some of the Sacred Texts do not associate Mary with Magdalena, while others do! Were there one Mary or were there possibly two? The texts must be interpreted and some say one and others say there were more than one Mary. Regardless of this The name of Mary was extremely popular at the time.

“Mary therefore took a pound of ointment of right spikenard, of great price, and anointed the feet of Jesus, and wiped his feet with her hair, and the house was filled with the odour of the ointment.” —John 12:3
“Mary hath chosen the best part, which shall not be taken away from her.” —Luke 10:42
“And when Jesus was in Bethania, in the house of Simon the leper, there came to him a woman having an alabaster box of precious ointment, and poured it on his head as he was at table. And the disciples seeing it, had indignation, saying: To what purpose is this waste? For this might have been sold for much, and given to the poor. And Jesus knowing it, said to them: Why do you trouble this woman? for she hath wrought a good work upon me. For the poor you have always with you: but me you have not always. For she in pouring this ointment upon my body, hath done it for my burial. “Amen I say to you, wheresoever this gospel shall be preached in the whole world, that also which she hath done, shall be told for a memory of her.” —Matthew 26:10-13
“And on the first day of the week, Mary Magdalen cometh early, when it was yet dark, unto the sepulchre; and she saw the stone taken away from the sepulchre...Jesus saith to her: Woman, why weepest thou? whom seekest thou? She, thinking that it was the gardener, saith to him: Sir, if thou hast taken him hence, tell me where thou hast laid him, and I will take him away. Jesus saith to her: Mary. She turning, saith to him: Rabboni (which is to say, Master).” —John 20:1, 15-16

Some associate her with the woman had seven demons driven out of her.
In fact it gets more complicated if we look outside the box and look at the private revelation of Catherine Emmerich. Although Catholics are not obliged to accept the Revelations of Catherine Emmerich, she is the one who ultimate lead us to finding the House of Mary in present day Turkey!
According to Catherine Emmerich, Lazarus and Martha had another sister by the name of Mary, who was not named in Scripture.
It is complicated!

The Family of Lazarus, Martha and Magdalen
The parents of Lazarus had in all fifteen children, of whom six died young. Of the nine that survived, only four were living at the time of Christ’s teaching. These four were: Lazarus; Martha, about two years younger; Mary, looked upon as a simpleton, two years younger than Martha; and Mary Magdalen, five years younger than the simpleton. The simpleton is not named in Scripture, not reckoned among the Lazarus family; but she is known to God. She was always put aside in her family, and lived altogether unknown...Lazarus ...looked much older than Jesus; he appeared to me to be fully eight years His senior. Lazarus had large possessions, landed property, gardens, and many servants. Martha had her own house, and another sister named Mary, who lived entirely alone, had also her separate dwelling. Magdalen lived in her castle at Magdalum. Lazarus was already long acquainted with the Holy Family. He had at an early period aided Joseph and Mary with large alms and, from first to last, did much for the Community. The purse that Judas carried and all the early expenses, he supplied out of his own wealth...The father of Lazarus was named Zarah, or Zerah, and was of very noble Egyptian descent. He had dwelt in Syria, on the confines of Arabia, where he held a position under the Syrian king; but for services rendered in war, he received from the Roman emperor property near Jerusalem and in Galilee. He was like a prince, and was very rich. He had acquired still greater wealth by his wife Jezabel, a Jewess of the sect of the Pharisees. He became a Jew, and was pious and strict according to the Pharisaical laws. He owned part of the city on Mount Zion, on the side upon which the brook near the height on which the Temple stands, flows through the ravine. But the greater part of this property, he had bequeathed to the Temple, retaining, however, in his family some ancient privilege on its account. This property was on the road by which the Apostles went up to the Cenacle, but the Cenacle itself formed no longer a part of it. Zarah’s castle in Bethania was very large. It had numerous gardens, terraces, and fountains, and was surrounded by double ditches. The prophecies of Anna and Simeon were known to the family of Zarah, who were waiting for the Messiah. Even in Jesus’ youth, they were acquainted with the Holy Family, just as pious, noble people are wont to be with their humble, devout neighbors. (Vol. 1, pp. 334-335)

Rome simply seems to desire that St. Mary Magdalen, St. Lazarus and St. Martha be celebrated on the same date within the Latin Rite.