After 3 days of trying, I finally called Yamaha, and they said it was common, and that a better method was available (though not in any manuals or guides). SO, if you are pulling your hair out trying to get your receiver and two speakers to connect for wireless rear surround sound, here is the EASY way (using a receiver and two speakers):

https://www.amazon.com/Yamaha-RX-V685-7-2-Channel-Receiver-MusicCast/dp/B07BZZCHGN