Facts:
...
True Names change in humans.
Do we know how often, or easily, the True Names change in humans, though? I don't recall this coming up in the canon stories; is there some nice clear WoJ?
Jim has been clear that two people cannot re-Soulgaze... WoJ provides an exceptional case: if one of them has undergone a wrenching, soul-redefining change (something exceedingly rare... Harry, for example, withstood a Fallen Shadow, and even
converted her, has became the Winter Knight, with the mark of Winter deep inside his spirit; he has
died (mostly (y'all know what I mean)). And yet none of these, singly or collectively, has changed him enough: everyone he has previously Soulgazed is still safe to look into his eyes). I suspect a re-Naming might take a similar level of change.
... I wouldn't be surprised if Michael knew Harry was coming back. I'm certain he is the type to have prayed about decisions as to Maggie's paperwork. (Whether to do it, what choices to make). And Michael often gets clear and direct answers.
If he knew, he would have chosen Dresden to help push Harry into accepting his responsibilities. Charity even more so.
Although, it's worth noting that the sorts of
Answers that Michael gets back are not always the most-obvious/expected ones. Maybe the whole Rodriguez/Mendoza/Dresden muddle would actually benefit Maggie to be
further muddled (in protective, hard-to-track-down ways) by giving her the Carpenter name. They wouldn't hesitate to extend their protection that way.