OK, finally an answer...

This doc, after reviewing my imaging, and the accompanying notes, said he has no clue how the others weren't able to figure this out.

It's essentially the same thing I had to have surgery for the the next morning after visiting the ER with swelling, fever, and pain back in June of '13 (
@Gabe1 probably remembers).
The difference being the first was in deep tissue and this one is not, so it is able to drain (for now) without a full-blown infection setting in.
Since I still have an occasional problem with the first area, he also (without actually saying so) alluded to the fact that the other surgery should have been done in a way that would have completely taken care of it the first time.
Anyhoo, this doc today referred me to another specialist (he was just the general surgeon on call in the ER that could not see me that day because he was doing emergency surgery) that he says will take care of it all once and for all. Her office is supposed to call me tomorrow or Monday.
Good grief, I can't wait for this to finally be completely resolved.

So, there's the update, and here's hoping...!