Without knowing V’s tendencies, hard to say how wide you 3! oop there, but it’s hard to give you KT.
Downbet lead on the flop doesn’t really tell us much. This kinda looks like a blocking bet to me, but you do claim you like to downbet a lot, so who knows?
It looks like the turn hit you, and you want to block the straight draw.
The check on the river looked too weak to be true. I would have checked behind and saved myself a tuff decision. I think he had enough showdown value to take the cheaper route there.
I would guess you had QQ.
There are a few other possibilities, like AQ or JJ or even AA, but V had blockers for all of them, so less likely. I don’t see many bluffs that can take that line on this rainbow board, so your tank-x! shove wins the day.
I mostly would have raised you on the flop, for what that’s worth.
NOTE: I am not limiting your SB 3! range to the hands I listed. Those hands were listed after taking in the context of the entire hand as played.