Can't add a specific organiser to a group

Odd error: I'm trying to make https://eahub.org/profile/sahil-kulshrestha/ an organiser of https://eahub.org/group/ea-bangalore/
But his profile doesn't come up on the drop down menu. (Normally I can do this if the profile is hidden, could it be related to his last name being changed to "~"?

