Ok using your assumptions: he's betting 88, 99, QQ, AA, AQ, AK on flop and never betting TT, JJ, KK.

6 combinations of 88
6 combinations of 99
1 combinations of AA
1 combinations of QQ
4 combinations of AQ
6 combinations of AK

he folds 99 and AK to our bet on turn and calls/raises with 88, AA, QQ, AQ.

So it's exactly 50% FE with this range. Now considering were extending his range to 88 exactly, which has a big impact given the turn card. What's to say his range doesn't stop at 77, or 99. Also if he ever c-bets with TT or JJ this further increases the FE. Pot sized bet on turn seems to be 0 EV at worst.

I think we've over analyzed the shit out of this hand.