I think perhaps there's something else going on with my Unraid install. Like plugins aren't being installed, period. I didn't realize this OS was so buggy. Moving to the 7.2 beta since what I have feels like beta anyway, and it's once again stuck unable to stop the array, despite installing the Dynamix Stop Shell plugin. Likely that didn't install correctly, either, and besides the "Community Applications" plugin, those are the only 2 plugins installed.