Last Summer, the Ashley Madison news came out - Cruz email addresses were in the company database. Not definitive proof it was Cruz himself, but not helpful to his case.
If you have an email address and it says Marsha@whatever.com, and I go to a site like Ashley Madison, and signup and use a fake address like news@whatever.com, I will still receive all mail with that address into my marsha@whatever.com, if it’s set up as a “catch all.”
It doesn’t matter what is in front of the @ sign, if you’ve got the main email setup as a catch all. I might be wrong, but I don’t think so.