Hi Habib,
Great question!
I’m afraid that Community Events does not have a setting that would allow you to prevent the number of events that are submitted for a venue. I am also unaware of any customization or snippet that would allow that to happen.
One idea might be to manually curate the events that are submitted by making submitted events Draft status by default instead of Published. That would allow you to review and edit events before they are published, including changing the venue.
Sorry I don’t have more of a concrete solution that fits your exact needs, but I hope this at least helps answer your question.
Thanks,
Geoff