Hi Mike,
While I haven’t used this yet, I too was thinking about how to use ULAs for active learning. I thin they can be listed as “co-hosts” once the meeting begins. https://support.zoom.us/hc/en-us/articles/206330935-Enabling-and-Adding-a-Co-Host
I was able to change this setting under “meeting (basic)” in my settings. Do you think this will work?