So, I was also having issues with compatability with unraid 7 betas and the release candidate
Just checked the community apps, and there appear to be 2 different versions of this plugin, both of which point back to this same support thread.
The one from "Squid's" repository does not appear to have been updated since December 2023 (this is the one I had), and the new one from "Reynald's" repository has only been created July this year, and has been updated much more recently, and it does include support for 7 and some additional features.
No idea if there has been an "official" change to the new plugin, but now that I know what to search the thread for I was able to find a few people saying pretty much the same thing.
long story short, I had to uninstall the old plugin (take a screenshot of your config so its easier to set up the new one, settings to not transfer across) and then install the new plugin, then reconfigure, and boom, shes all good again.