Fair enough, communication could indeed be improved. NAL but I was under the impression that, while they could surely be more helpful here, once they received that official DMCA takedown notice they don't really have a choice in the matter of taking it down or not.
Edit: disabling the repository after being notified by you within 24 hours seems to be against their own policy at https://help.github.com/en/github/site-policy/dmca-takedown-... - have you tried contacting their support again?