Help me help this snake

I posted about the snake I'm rehoming for a friend, this poor thing has a terrible setup and I think might be sick. 4 years old. Had this same set-up his whole life. Eats live rats, hasn't eaten in 3 months. Has cedar bedding, overhead lamp, no UTH, no night heat source. Stupid tree branch thing with screws sticking 3" out of it. He's making squeaking noises and sits with his mouth open, and seems to have lots of "spit bubbles" and breaths loud.

I'm swapping out his bedding with the bark bedding I use, my husband is fixing the screws, we hot him a red heat bulb for night so we can turn off his light to give the normal day/night cycle. Since he just made a travel to my house, I'm giving him a few days to adjust before I try to feed. I also have no reptile vet anywhere near me.

I'm doing someone else a favor of rehoming because their kid left for college and can't take it with. Quite honestly I'm very torn between not investing much $ on this snake that I'm not keeping and spending the money to do what I know is right for this poor guy. Any suggestions????