I tried sending again with the form and got the general error "There has been a critical error on this website."
This is the post I'm trying to send in case you want to debug or try re-sending the webmention: https://gregorlove.com/2022/05/open-mentions-is-an-interesting/
Responses★ Matthew D. Brown 🔶🤎🇺🇦,
I got it to work. Now to contact the plugin author and confess all the bad things I did to it.