Hours-long daylight firefight could be what happens when the enemy is closing in on the downed guy in daylight, and you can't wait. You have the fight you have to have, not the fight you would prefer to have.

Even if the mission was actually about HEU, I don't see why that would lead to the destruction of the aircraft. Why not just fly them out again? So I suspect that they really were stuck. If they were, they would be destroyed regardless of the purpose or mission, to avoid Iran gaining intel or materiel.

I won't comment on the rest. I will note, however, that if the airman was in Boyer-Ahmad, a US raid in Isfahan would be quite a diversion. I will also note that Trump barred the press right about then.