Thanks for the heads up!
When I first had a look I wondered why these had been upvoted by @dustsweeper, none of them had an account and neither had the upvoters.
It was actually caused by a bug and triggered by one of the downvoters... :(
A user with a dustsweeper account, set to protect outgoing votes, would trigger this bug if they downvoted a post and if the post was still above 0.

So far I've only seen @shmoogleosukami impacted by this.
I will do a scan of all votes since the outgoing votes were implemented and refund the users.