Kev Quirk@nolan we're having the same problems on Fosstodon. What @mike and I ended up doing, was killing the registration, and replacing it with a link to a form that emails us. We can make a decision and provide them with a one-time invite link.
It's not perfect, but it's an unhappy medium for now. Have a look at ours. If you want me to package up the form etc. let me know.
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