would you fold this?

[sh58]

Party Poker No-Limit Hold'em, $2 BB (6 handed) Party Poker Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

saw flop|<font color="#C00000">saw showdown</font>

MP ($281)
CO ($281.50)
Button ($188.75)
SB ($183.03)
BB ($229.30)
Hero ($231.55)

Preflop: Hero is UTG with xx
<font color="#CC3333">Hero raises to $8</font>, MP calls $8, <font color="#CC3333">CO raises to $30</font> with KK, <font color="#666666">3 folds</font>, <font color="#CC3333">Hero raises to $75</font>, MP folds, CO calls $45.

Flop: ($161) 7[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/diamond.gif[/img], 8[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero shoves for $156.55 (All-In), CO folds.

Final Pot: $392.55
<font color="#009B00">Main Pot: $392.55, returned to Hero.</font>

after this pot villain told me he folded KK and i believed him. he was playing 19/12 over datamined hands.

would you fold if you were him. we haven't played much before, so he probably views me as a TAG, i had probably played 30 hands at the table running at about 23/19