I think hed show the bluff, because you did previously. Telling you the truth but leaving you wondering tracks for him actually having it.

I agree on the overbet thing

Obviously I think you made a good fold.

Knowing he has the Ac, and if he actually has a Q, then we'd be calling to chop 2/3 of the time and lose 1/3 of the time. The rest of his range is either AXcc, or AcXx, and I think his line, his exposing the Ac, and his speech play are more heavily weighted towards value than bluffs.

He has showed bluffs that got through a lot recently, so that is decent.

No doubt he would have shown a bluff, having already showed you the Ac. Not showing a bluff would defeat the purpose. Mucking his cards face down when you made a good fold is in alignment. He wants you to wonder if you made a good fold, not know you made a good fold.

You can of course run some sims and see what a solver would do here. But to me, this all really comes down to logic and psychology.

When he shows you the Ac, his range becomes entirely polarized to nut flushes and bluffs (putting AQo into the bluff category). His donk over-bet is polarizing. Showing you the Ac reinforces the polarization.

But he's MUCH more likely to show you the Ac as a way to induce a call when he has it, than to show you the Ac to induce a fold when he doesn't. He'd want to reinforce the polarized nature of his over-bet when he wants you to call, by making you think he might be bluffing. He wouldn't want to do that if he actually was bluffing.