Hey Ken,
Before any further investigation here, I think resolving this discrepancy is the most important first step:
I am running a multisite with a single activation of The Events Calendar (not pro) and Community Events on a subsite.
You should make sure that the plugins are activated in the same way, so that either The Events Calendar & Community Events are both network-activated OR they are both sub-site activated together.
Does anything improve if you assure this is how things are set up?
Thanks!
George