Yes he'd hire him again. He was about to get fired if the basketball program didn't improve and he made an embarrassing hire with Gillespie.
Where he and all AD's make mistakes is not understanding these HC's often go for "hugs" when they are depressed and realize they are losing their fastball. Iowans would freak out about losing Kirk Ferentz. Why? This is a control freak dickhead who can't handle the Iowa media being critical but he'd seek to go to the NFL or a bigger job and handle scrutiny? Bob Stoops often would leak he was looking at the NFL or another job-and he was very overly sensitive as well.
With Cal there were 2 reasons I'd have called his bluff. Cal's wife is not going to seek LA at this time of her life. It's away from all of her kids, it's a massive city and nowhere does it resemble a college town.
Secondly, Cal's ego of being in a city where he's not the biggest show in town would never fit. He couldn't handle being 5th/6th fiddle. He is frustrated with FB team getting preferential treatment in Lexington, how would he handle being behind the Lakers, Dodgers, Rams, USC Football, Clippers, Angels in terms of importance? A UCLA home game resembles a Covid era gathering. Mitch panicked because he's about as far behind as it gets and did the deal.
At this point you whack both of them whenever it's happening. One can't stay-both have to go.