There's just a decent likelihood that in the past two weeks some sort of dispute has been made about this. Maybe the original owner contacted them, and they are trying to decide what to do about it?

If there's a dispute on something that I don't know how to resolve, just disabling it until I get advice from a supervisor sounds like a good strategy to me.

That article was posted 10 days ago, on a US public holiday. Seems likely the previous owner only recently reported an account "theft" enabled by github's own support team and name reuse policy. This is exactly why account name reuse is such a bad idea.