My coach is a 2001. I had to completely redo the brakes in my first year of ownership (2017/2018). My rotors were cracked, some of the abs sensors were melted, and the brakes were sticking. The cause of the sticking (I believe) was corrosion and gunk from the brake fluid that had been sitting in the system for years. Even after I changed the rotors, calipers, fluid and pads, I would notice a wheel running hot (much like you describe). The first time after the brake job that I went to change the brake fluid, the driver's rear would not bleed. Then I noticed that the rotor on that side was rusty - obviously the brakes were not working on that wheel. I went to a shop with a computer and the Cummins software, and the analysis found that one of the solenoids in the ABS modulator was not working. The modulater was replaced and I have not had any trouble since then. I offer this only as my experience. Youir situation does not seem to exactly match mine. I would encourage you to bleed the brake system until you have all new fluid. When you do that, inspect the rotors to verigy that all wheels have been working.
The braking system on our coaches is proven and reliable (on school busses and medium duty trucks) as long as it get regular use. Unfortunatly, RVs tend not to be used for long periods of time, which contributes to the brake fluid/corrosion issue. It is considered good practice to change the brake fluid at 2 year intervals.
After studying the layout of the brake sustem on our coaches, I decided that it didn't matter which wheel you worked on first. The first wheel will take at least a big bottle of fluid to get new fluid into the master cylinder and the line ot the ABS modulater. After that, you are just clearing the line to each wheel.