That's a long time to wait if something is happening in the cabin.
Um, in this case, shouldn't the Captain talk to his own
cabin crew to see what was happening
in the cabin?
Did he? What did the FAs told him? "All clear!"? or "Smoke is chocking us to death!"? Or did the Captain made his decision in isolation?
Just more parts of the puzzle we don't have.
The full facts might completely be in favor of the Captain. Or they may throw big doubts about his claims in front of a jury. We just don't know.
Lastly, this incident happened at the tail-end of a tough labor action from the pilots's union. Did that affect anything, e.g., Allegiant's
perception of the incident?