Two remotes per fan with multiple fans?

I have seven fans in my house, and I want 3 of them to have 2 remotes each (and the others to have 1 remote each, no multiple-fans-per-remote going on). I’m using the model 99434 kit from Home Depot that was recommended on another post as having discrete on-off signals for the light. I’ve gone so far as to order 3 extra remotes from support, only to find that when I installed my first fan and paired a second remote to it, it forgot the first remote. How can I fix this problem?

I believe this kit is technically made by Hampton Bay - have you called 1-800-330-3267 to see if they can give you options to pair multiple remotes to one receiver?
I believe I had the same experience with this kit in that pairing a new remote ‘forgets’ the other one, but I didn’t spend much time with that effort, as one remote is fine for my use case.