You can do a local recording with zoom, you can have a meeting by yourself, share screen, and then position the camera where you want it, and record. when you finish the recording and the meeting, the file will be processed and saved on a local folder without doing anything else.
I consider that the easiest method.
As far as I know, CasaOS (same as Cockpit) is installed on top of a default OS install, so you could always access the OS directly to install/configure things outside of it, if the need arises.
I would not say you would be held back by it, if it does what you need. And for what I can see online, you can install any docker container even if it’s not on the default catalog of CasaOS, or access the OS.
If you want to grow your knowledge of how things work, or how to deploy services without CasaOS, you can always do so in parallel of using CasaOS, so I don’t see where the issue could be.