If it is a bluff villain isn't as passive as you think. Villain is either more aggressive then they seem or a bit of a spazz. He is bluffing into 2 opponents, either of whom could have checked a ten on the turn. At the same time, it's unlikely that hero or button would have checked a ten on the turn. They have better reasons to bet then a blind does.
Of course it could be, but I doubt he's bluffing at anywhere near the frequency you can pick him off this sort of bluff effectively.
The one caveat is he could have an overpair (if that's in his limping range), and think he's good, but you would know better if JJ+ is in his limp-call range.
I have seen a lot of players that i thought were loose passive make bluffs like that. Is it a bluff often enough vs pot size bet though? That I dont know. But ive been surprised plenty of times when someone I thought was passive potted the river after turn checked around and showed 96 here.
