Someone always appears to know less than you do.
Heroes Museum? Or Super Heroes Museum?
Marvel has at least one convenient registration.
DC and Marvel apparently assert trademark rights.
Plus, it makes no sense. The logo and domain name don’t match the “Super Heroes Museum” text used throughout. You’d suspect small changes from a c&d, except that superheroesmuseum.com is unregistered, which points to just inexplicable inconsistency. Say, go register that domain name…