5-10 NLH at the MGM -- Villain wants a ruling

[Rococo]

This hand had some interesting psychological elements to it. Villain in this hand had approximately $2K. I had him covered. We have been playing together for approximately 30 minutes. Villain and I haven't tangled yet, but he seems from the table banter to be a Vegas regular/grind it out pro. He has not gotten out of line yet, and I'm sure that he believes that he is better than me. The only hand that he has seen me take down was a flop semibluff where I made the nut flush on the river.

I make it $50 to go preflop after one limper with
A[img]/images/graemlins/spade.gif[/img] Q [img]/images/graemlins/heart.gif[/img]. Villain calls in the BB. Limper calls as well.

Flop

K [img]/images/graemlins/spade.gif[/img] T [img]/images/graemlins/diamond.gif[/img] 6 [img]/images/graemlins/spade.gif[/img]. Villain checks. Limper checks. I bet $120. Villain calls. Limper folds.

Turn ($390)

2 [img]/images/graemlins/club.gif[/img]

Villain checks. I fire barrel two for $300. Villain looks at me and says to the dealer, "Only $100 of that bet made it past the bet line. I want a ruling on whether the bet was $100 or $300." The dealer looks at me to see if I plan to say anything in response.

Given my marginal holding, what is my play here?