mhf_alex should default to mhf_alex if skin not accessible
mhf_alex should default to mhf_alex if skin not accessible

We only use the 'hard stored' mhf_alex skin when it's part of the 'default' query parameter.
In the rare event that mhf_alex is requested but the skin is not accessible, we would fall back to 'mhf_steve' because it's the default for usernames.
This commit adds the special case to use the stored version of the 'mhf_alex' skin when it's not accessible otherwise

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