I feel like I'm missing something obvious, here.
I accidentally committed some huge files.
Fair enough.
I went through the remediation link and ran through the process. The files are no longer shown in the repo (I only have the single branch).
The docs say, contact support to explicitly run GC on my repo. I tried contacting support but the contact option is greyed out and I'm apparently only limited to community answers.
This is despite the fact that this is likely a systems problem that requires intervention from an administrator.
This is admittedly my fault, but this entire process has been extremely frustrating since there is no self-help option but I'm not special enough to have a person pay attention to me.