Top mod inactive in subreddit, left posting locked, unresponsive to modmail

I'm a mod at r/ritcirclejerk, the top mod has sdubois has been inactive in the subreddit for well over 2 years, and has not responded to any of my unlock requests in modmail. This user is a supermod, and as such, probably doesn't want to turn on a shit posting subreddit and have to moderate it. As such, I'd like to have them removed and "top mod" duties applied to all the mods that are currently there.