"This is not even considering that the attacking fighter would have been identified by an E-3 and picked off by fighters flying CAP long before it could even detect the A-10 in the weeds."
Of course not, because if we did, than we might as well argue that the MiG-29 would never be anywhere near U.S./NATO aircraft because most would be destroyed on the ground by stealth bombers, cruise missiles and other offensive means. Those that won't would surely be destroyed in BVR conditions by AIM-120-equipped air superiority fighters.
You mention the A-10's good manouverability, but I don't see that as being the case. The Warthog can sustain a turn at a max rate of about 12deg/sec, while the MiG-29 can do about 24, even if the A-10 is able to maintain a far smaller speed the MiG-29 will still have the tighter turning radius. As for speed, there is certainly a difference in minimum speed, in favour of the A-10, but this is where I believe the HMS/AA-11 really comes in handy. After all, the greatest rate of closure between a fast moving MiG-29 pursuing a slow moving A-10 would be when the Fulcrum is flying in the same direction as the Warthog, which doesn't have to be the case for a succesful Archer attack. I have no doubt that even a highly skilled MiG-29 pilot (which most current operators of the type lack in sufficient proportions) would take a long time and several attempts to get a good shot at an A-10 nevertheless, which is where the Fulcrum's awfully short legs come through as a distinct disadvantage. The -29's dark black engine exhaust is not very helpful in a close-in fight either.
Seeing as the A-10 has neither a maneuverability nor an energy advantage over the MiG-29 the Fulcrum pilot would have a significant moral advantage. After all, he can always make a safe retreat.
All of this is of course based on a very theoretical 1v1 dogfight scenario, seeing as a more realistic approach would be far too unfair and, well, boring.