@darius i wonder if there'd be a way to let the mastodon user generate a short hash that they just need to place someplace on the page (maybe even temporarily?)
like maybe i can't modify html in a page on my institution website but i can copy a hash string, place it at the page at the foot of the page, and then verify (maybe even let me place it temporarily if my IT admin doesn't like it; then you might want to say "last verified 6 weeks ago" or something)