Maybe I don't understand the complete problem but it seems like you are making it more complex than it really is. When the receiver in in Single mode you can control it using both remotes (IR and RF). So in Single mode you use the IR in the den and the RF in the other room. Then when you switch to Dual mode, you keep the same remotes in the same rooms because TV1 is controlled via IR and TV2 via RF. It just works. Do you have a different experience?