Hi,
1. The issue is probably caused by the cache plugin you are using, probably something with the configuration. I am not seeing some of the inlince scripts on the page, which causes the problem. This does not seem exclusive to this plugin only, I am seeing multiple inline scripts missing.
Try looking on the cache plugin configuration to something with “inline scripts” or “merge inline scripts” or something like that, and try turning them off.
2. If you are running a multisite installation, then installing the plugin on the main network admin site will make it available on all sites.