UTg vas a fish, around 65/20, MP was a player with 56/22 from 9 hand sample, so pretty much unknown but not a regular.

I hit a middle set on a board with lot of straight draws. It is checked to me so I bet, I usually bet around 80%, so I keep the betsizing similar.

I find this betsize to be very odd, but it is coming from 60/20 fish. I really doubt that he doesn't have AA, because he limp-called preflop. That means that my set might bet best at the moment. The question is am I facing J9?

Would my opponents really bet less than half a pot when board is superheavy from draw if they had nuts?
I could call of course, but if I call, it would be very hard to trust my gutshot if J will come. MP most likely has some kind of draw. If he has KQJ, My Q9 is not alive against J, because that would make KQ to get nuts.

After thinking a while I thought that maybe there is 69 I can get to fold and if I get called by that or by nuts, I most likely have my gutshot alive. And if we go All in 3-way, I have a reasonable equity even when UTG has made straight.

Was it correct to raise this all in?