I'm not an expert, but I'll tell you what I know and ask you some questions.
What are the temperatures in the tank and what are you measuring them with? We need three different temps; the cool side, the hot side, and the basking temp.
Im not sure what you lights are like but need a reptisun 10.0 for the UVB. I didn't see one mentioned or maybe I did but overlooked it. For you heat light, you can use a regular household bulb from home depot. Make sure they are bright white though but they are so much cheaper.
I would suggest taking the heat rock out of the enclosure. The reason is because dragons get their heat from above them not below them. The heatvrock could burn them without them even feeling it.
As for the possible impaction, there are several things you could do. You could massage his stomach in the bathtub, feed him unsweetened applesauce, feed him canned pumpkin(Not the kind you use to make pies, just the regular stuff) or you could feed him prune baby food. make sure that no matter what method you use, keep him
hydrated.
I would try to cut back on giving him crickets, I know you say he doesn't eat them, until he gets a poop out. Until then you could feed him chicken or squash baby food. I prefer the chicken since the amount of protein is higher and he's you'd so he needs the protein.
I'm hoping someone more experienced will come along and offer better advice.