It's called WebEx, and it's what a different meeting of mine was on today. Since by now I have a microphone, if still no camera on my desktop (and I'm not planning on getting one), I could sign in hard-wired without suffering through my tablet on wifi. I'd found Zoom's interface to be cramped on the tablet, so it's not fair to compare that to WebEx on the (much larger) desktop, but I did figure out how to work the commands, and the tile display got all 11 other people in the meeting on one screen, even the others who had no video (who'd mostly telephoned in), so their displays were blank.
Video displays were pretty good on WebEx, but sound was variable. People who came through loud and clear on incidental remarks suddenly started fading in and out or getting caught in transmission stutter when they had the floor and spoke at length. But most of what they said came through.
The curious thing was that, unlike with Zoom, I had no visual display for myself (even though there'd be nothing on it), and, even more curiously, I could not hear myself on the headphones, though others assured me they could hear me. However, if there's any measurable delay in sound transmission, which there probably is, even a fraction of a second, it would be best not to hear yourself, as to hear yourself speaking live on even a small delay is a good way to make you trip up on your words. It did mean, though, that there was no way to tell if I was emitting background noise or (unlikely as it'd be in the circumstances) feedback.
Anyway, now we know the microphone works, both in itself and in persuading the computer and the meeting software to go along with it, that's the important part. So now I can go ahead in planning the matter that I bought it for.