Halfway to disaster? How to Protect iCloud Drive contents after deleting files from local copy with multiple OS installs

1. How can I protect iCloud Drive contents when deleting files from a mac ***with multiple OS installs***, i.e. from a offline local copy? I have multiple macOS installs on my Mac. I think, some time ago, without thinking through the consequences 'till now, I may have deleted "extra copies" of some large files from iCloud Drive in one of the offline installs - but **not** the main one that is currently booted. I'm thinking that if I log into the copy of macOS with the "extra copies", the mac will sync with iCloud, and thereby **delete the files from iCloud (the cloud copy)**. **2. Correct?** (And I presume later, when I log into my main OS, it will delete them from that install's local copy too - assuming there even is a locally cached copy. **3. Correct?**) 4. Assuming I've already done this - deleted "extra copies" from an offline copy of the OS - how can I prevent losing the other copies? Way to detect that I've done this? I presume there are a few ways to do this, wondering what the best are. I suppose I could delete and never use the other OS installs, but I'm looking for a less brute-force option. 5. Is there a way to tell the OS not to trust the local cache? I guess this is a variation of the issue where people delete photos from devices sync'd with iCloud, ignoring the warning of the consequences (the warning). But on MacOS, there's no such warning - it's presumed the user knows what they're doing. I may have been smart enough to turn off iCloud Drive while logged in to the other OS before deleting stuff, but I'm not sure. That would have been the smart thing to do. Note: I have NOT activated iCloud Drive for "Desktop & Documents" on any of the installs. I have for everything else.