Earlier quoted context omitted.
The maintainers of the previous repo didn't get a chance to file a counter-notice. That's why many people are upset at github about this, they took down the repo (and all of the forks, I think?) as soon as they received the letter from the RIAA.
You can file a counter-notice after it gets taken down, and then the repo will be reinstated. That's my understanding of how it usually works.
According to the DMCA, the entity that files a counter notice consents to jurisdiction of the US district court of their residence. If not a resident of the US, jurisdiction is the district where the service provider is located. Once a counter notice is filed, one cannot argue the law doesn't apply because of lack of jurisdiction.