Without actually being there and having watched this guy, its impossible for me to say if I'd make this laydown or not. I can say there are enough ingredients to fold here under ideal conditions, particularly live where you have time to think.
By how you describe this there are at least 5 players in this pot, which he raised to $6 PF. So, when he reraises your $45 to $100, this pot has at least $175, and you need to put $55 to call, which is giving you better than 3 to 1. As you put it, he priced you in, so his reraise is begging for a call. What hand would do that? Well, that's the big question that we need to answer.
Lets start by looking at the board. Its very coordinated, and also has a flush draw. In brief, a dangerous board. Would trips really do this on that flop? Maybe. I think if you have trips on this board, even trip Q's, and your flop bet gets reraised you start wondering if you're beat. Although that's not enough to fold, you wouldn't make such a small reraise like the one he did, because even if he could suspect you're drawing he can't be sure of that and he won't find out anything with his $55 more because you're priced in to call with any draw if you count implied odds
. When you consider all this you have to conclude that trips isn't likely, with few exceptions that I'll discuss in a bit.
Its also improbable that he has J8, the same hand you have, because of his UTG raise PF. And top pair, like an AQ hand, would be concerned with your raise.
Does it mean he HAS to have KJ? No, it doesn't, but you could start to suspect it. Even if KJ is not a great hand PF, he still could raise with it even from UTG, I don't see why not considering what some people raise with, particularly if its zoooooooded lol. Plus you forgot to mention if its full table or shorthanded, so I can adjust raising range accordingly. There are other possible hands, like AdTd, but it wouldn't explain the minreraise, nor would any other flush draw, and same is valid for AQ. KJ really looks like the most probable, with the chance its a set. So, lets go back to that, adding a couple more considerations.
The first is any read you have on this player, but even more important is the table image that you have. Without these 2 its impossible to really say if I'd lay down or not. At times your image is even the biggest factor in this because if you'd been LAG and raising a lot or just very aggressive with top pair and draws, then I can see a set playing like this, trying to get you committed and taking the small risk of getting outdrawn on that board. If you haven't really raised much, if you've been tight, then, even if he can't pinpoint you so early on a made hand, he would proceed more cautiously rather than trying to commit you. In that case, his raise means KJ just about 100% of times. I really think that in a hand like this, with the raise he made, your table image and the way you are percieved is more important than any read you have on him. That's not to say what you think of him doesn't count, I'm certainly not going to discount it, and some of the same considerations that were made on your image apply to him also, such as how aggressive he plays the flop, etc
For his possible range we have to include overpairs to the board, since he raised PF. Here's where your read on him also becomes important. Although an overpair wouldn't play like this, that flop minreraise I intend, with some players you never know. But I see that in your thought process, where you tried to read his hand, you never mentioned it which makes me assume you thought he was a better player than that.
In conclusion I did all this writing and I'm not able to tell you if I'd lay this down or not, all I can say is that under some circumstances I might of, in others not.
I will say this though: next time fold J8 PF, it saves trouble and money buddy, way more often than not. I didn't want to start my post with that because I know you wanted to discuss the hand, and not your PF decision to enter this pot. But it shouldn't take away from the argument that you're better off to fold J8, especially OOP like you were. A case can of course be made if you have position and you think you can outplay them, or if you were LAG the whole time and it was working good for you.
GL on your next trip.