Can the admin find out the mail to which the letter was forwarded when clicking on the link in this letter?

Question

PHP

There is a mailbox [email protected] which receives notifications from the site, for example, "You have received a message" which redirects this letter to [email protected] Does the site administrator have the opportunity to understand that I have already clicked on the link (which leads to the site) from mailbox 2, and not mail1. Those. to learn that address on which redirection is carried out?
ps ip address is already different, so now only the issue with emails remains.

Answer 1

No. Headers of letters are not transferred anywhere further.

Answer 2

Everything is written in the heading of the letter. All redirects.