Well, it's sort of absurd to ask for an official holding of something so blatantly obvious as this. But sure...
Here's
a whole string of Supreme Court decisions, which basically operate on the principle that:
In this case, the private party was explicitly hosting a public forum. If anything, the fact it was a non-profit religious organization puts more requirements on the host, not less.
In those cases, the host must ensure open and non-partisan access to the event for the public.
Filming a public event is consistent with that, and throwing out one man who was filming while not throwing out another man who was filming is not.
And just as a general proposition, this seems a pretty absurd thing to argue about or object to. Really, it's the most mockable thing in this thread I've seen, if it weren't symptomatic of so much that's wrong. If folks want politics to get better, they could start be extending the golden rule when it comes to basic discourse.