i wouldnt like that turn one bit... based on the lack of info you had on the player at start of hand i'd be concerned.

two most likely hands he capped pre-flop with and would check-call that flop are: AK and QQ in my opinion... either way youre a serious dawg at this point

i actually like the check on the turn in hindsite, although i think i'd possibly charge here... who knows what utg has at this point... given its 2-4 party poker, i wouldnt rule out K-10 or flush draw...

from the river play i believe you won the pot over AK, and possibly K-10 from utg...

but again, i don't fault your play on turn one bit even if i may have done differently myself...