You didn't overplay your hand at all.

I like the 3bet pre flop and the size was great.

As played, I'd have bet 3 streets smallish.

$5 on the flop, $7-9 on the turn and then I'd ship the river. UTG can be calling with a wider range pre flop as there's 2 people left in the hand who they make expect to call along.

Without knowing more about UTG, I'd have bet 3 streets fairly small. GG if they turn up with KK-AA but I think they shove pre flop most of the time than calling give the action.

I would probably have played it the same, but do we have to shove the river or can we do something non standard? Once we shove we're just blindly expecting villain to call it off when he's chopping at best. It feels like something's wrong with the line. Maybe just c betting keeps things simpler.