I think you can check the HTTP_REFERER header and block the redirect using your back-end code, like PHP or Node or Python, not sure what tech stack you are using.
The user's browser will display a redirect loop error; and most importantly, they won't see your domain.
It keeps your name out of it and makes the email domain look even more fishy.
I don't know why everyone seems to think that HTTP redirects are visible in Referer (or Origin or any other header), but that's just not the case: HTTP redirects are completely transparent to the destination server.
They would be if it's a same-origin redirect, no? And I was under the impression that 3xx also set it cross origin (barring a referrer-policy header), though I'm less confident now. (I can't test it ATM).
Edit: I am clearly confused. The browser preserves the original referer when performing a 3xx, as you said.