First off, welcome to iRV2!
Second, you should add a "signature" to your profile. It contains whatever info you want; most people put info about their coach there, so they don't have to type it into each message. Instructions for adding a signature are here
As for the fuse, I should first say that I went astray a couple years ago when I was trying to help someone with a 2011 HR. I assumed it was wired like our 2008. As you have found, the newer HRs appear to be wired "the Fleetwood way."
That said, your coach's Ford fuse #5 serves the same purpose on your coach as it does on mine: to provide a 12V source with the ignition switch in ACCY or RUN position.
If your fuse #5 is blowing, then I would suspect a short downstream of the fuse.
REV Group (the company that made your coach) should be able to provide you with wiring diagrams that will help you troubleshoot. Their telephone number is (800) 509-3417 or (800) 435-7345, Monday through Friday.