Why did they write a comma here? I think I understand this sentence correctly, but the 4th comma puzzles me. Is it necessary??

在当当网，“创新”是全方位，而俞渝就像心脏一样，源源不断地把创新的血液，输送到企业每一个环节。
I think this is:

在当当网，“创新”是全方位，而俞渝就像心脏一样，源源不断地输送创新的血液到企业每一个环节。
In your first sentence, the 4th comma is indeed unnecessary. This is what I would write:

在当当网，“创新”是全方位，而俞渝就像心脏一样，源源不断地把创新的血液输送到企业每一个环节。

Your second sentence is grammatically correct, but using the 把 construction is much more natural.