Hey @LorenAmelang + @awelzel ,
Thanks for bumping this topic.
I did bring this up a few weeks ago during the Collabora Community Weekly meeting.
And, just today, I was talking to a Collabora developer + randomly made him aware of this zoom issue. (He seemed very interested!) 
Edit: Looks like he posted his findings:
Good news too, Calc is going to be a major focus for the next major version of Collabora Online, so many devs will be adding new features + digging through the Calc/spreadsheet backlog.
(As always, see the Github for the latest changes. But now that I’m aware of issue 4250… when it gets fixed/squished, I’ll repost info here.)