UTG is 53/24 over 14 hands. MP is 19/13 and is yet to 3 bet over 20 hands.

This 3-bet is celarly never a bluff and could even be a range as tight as [QQ-AA AK.] The probolem is that a cold 4-bet here looks insanely strong and will likelt fold out everything but AA and KK which I have terrible equity vs. I decided to flat for this reason.

Now the flop is where I just wanna make an extremely nitty fold. I feel like there are exactly 2 hands he can commonly have here once he raises this lead on this board multiway - AA and QQ. AA seems more likely as someplayers don't 3-bet QQ vs utg opens much although I think vs this guy anyone should be. How abusrdly nitty is this fold?

No-Limit Hold'em, $0.25 BB (6 handed) - Hold'em Manager Converter Tool from FlopTurnRiver.com

CO ($38.30)
Button ($22)
Hero (SB) ($37.25)
BB ($27.10)
UTG ($14.90)
MP ($25)

Preflop: Hero is SB with K, K
UTG bets $0.75, MP raises $2.25, 2 folds, Hero calls $2.15, 1 fold, UTG calls $1.50

Flop: ($7) 8, 6, 10 (3 players)
Hero checks, UTG bets $1, MP raises $4, Hero folds, 1 fold

Total pot: $9