Hello Aaron Kasatkin,
Based on your description, this does not appear to be a problem with the Microsoft Family app installed on a device.
Microsoft Family membership is managed online through the family group itself. Uninstalling the Microsoft Family app or changing OneDrive settings will not remove an account from a family group.
If the family organizer account has been blocked and is no longer able to manage the family, there is unfortunately no documented self-service method for another family member to remove themselves from that family group when organizer permissions are required.
At this point, the best option is to contact Microsoft Support and explain that the family organizer account is blocked and you need assistance with the family-group membership.