Lippert Industries has been buying up "RV parts manufacturing companies" for the past 10-20 years. As they grow, they tend to find bigger parts manufacturers to buy. Through the years, Lippert has become a major supplier of nearly everything "RV manufacturers need".... So, even though your system was "designed, built and marketed by a different company" it now probably belongs to Lippert.
My 2014 Cougar has a similar "remote control system" to yours. Most of the parts are obsolete, and about the only place to find them is in salvage yards and/or on EBay or places like that.
Lippert does have a website where you can get information on the older systems and the current (soon to be obsolete) systems that replaced them.
https://support.lci1.com/electronics...-and-receivers
Download the Lippert pdf and compare the "past to the present". You'll probably find your system and with the contact information on that link, you should be able to get enough information from Lippert to determine if you're trying to revive a dinosaur or if you might actually be able to still get parts to make the system work...
Worth a try, even if you do hit some snags along the way...
GOOD LUCK !!!!!