You can check my signed message which verifies my ID on this Mastadon instance here:

https://gist.github.com/jimmysong/46fc6ddce20b4f99072e939f1566b8ca

@jimmysong Is there a copy of your PGP key somewhere? Keyservers are kinda busted these days, so you have to manually upload to a keyserver, or provide it somewhere yourself.

Eg go here and click on "Submit Key": http://keys.gnupg.net/