Please help, Severity A tenant lockout still unresolved, not sure what else to try

I want to be upfront that I've posted about this before and understand the concern about repeating myself, genuinely not trying to spam, just running out of options and could really use guidance. Our tenant has been without any Global Administrator for over a week now, case TrackingID#2609100040007599, Severity A, verification fully completed on Microsoft's side since 9/11. I've tried phone support, the ticket thread, and posting here, and I'm still stuck. If anyone can point me toward the right way to get this in front of someone who can actually act on it, I would really appreciate it. Happy to provide any details needed.