EDIT: After more digging, I found the contact, the terms of services here https://docs.github.com/en/site-policy/github-terms/github-t... are linking to this legal section here https://docs.github.com/en/site-policy/other-site-policies/g... that contains address and email for legal requests. This is incorrectly put in a page "Guidelines for Legal Requests of User Data" but it's not about data request, it's for all legal requests.