[desmosxxx]

You're wrong. The reaction to the email and apology from Princeton is proof of that, but there are also very few people here agree with you. I'm not a lawyer or a business man and I read the email as a clear legal threat. I had anxiety just reading it, the same as the OP.

It's clear as day. And if for whatever reason you don't see it that way the rest of the email and the way it's written should set off alarm bells as being a potential scam.