Tank set up actually looks pretty good, the better gauges will just make things easier for you to measure and more accurate too. It may come down to your food choice and when & where you're feeding. Rat pinkies are really tiny and from the looks of your snake, probably too small for him. I don't suppose you know the weight of you BP? It tends to be the best way to determine food size. As an example my HRA Super Pastel Lesser girl was taking f/t rat pups when she was 177 grams.
A couple of other suggestions on feeding, you may want to try feeding a small live mouse to him in a separate tub. I only say separate tub not because of the whole feeding aggression debate but for simplicity and so your snake knows right where the prey is. I have one BP that hates hunting them down in his tub so I take him out and feed him in a separate tub and he's perfectly happy. If I don't take him out and just drop a mouse in his tub I can come back a half hour later and the mouse is still running around! The other things to try could just be your timing, wait till night time to feed, or wait till you see him in his hide with just his head sticking out (he's in hunting mode). Also if you're panicking that he's not eating are you trying again every night? If so you're likely stressing him out. I was guilty of this mistake and learned the hard way to just trust the boards here and if they skip a meal don't present food again till the next time they are scheduled to eat.
Hope one of these ideas helps.