Follow up …
Wahoo’s response was to make sure TR was up and had the Kickr locked into BT before trying to pair the ELEMNT to the Kickr via Ant+. I was already doing that, so I went back and tried again.
The reason I was going in circles was because on the ELEMNT, I was selecting the “Forget Sensor” for the Kickr thinking that it was releasing the BT connection as well. Guess it wasn’t because after going through the “Forget Sensor” option, I powered down the ELEMNT. Once I restarted the ELEMNT and went through the “Add Sensor” option, the Ant+ connection worked.
So during my workout, I was able to use the head unit in Ant+ mode for the Kickr, HR, and Stages PM while TR was being used with a BT connection to all three pieces. I was hoping to use the Mode option on the head unit to switch to resistance mode during the rest intervals, but that didn’t work out because BT wouldn’t let Ant+ control the Kickr for more than a couple of seconds. Oh well. I was able to do other things with the head unit, so glad it worked out.
Thanks again, @Bryce!