You should sue whoever you have a contract with since you don't have a contractual business relationship with anyone else. Once you get a judgment, you can then issue garnishments on the Prime and possibly Cox and anyone else that may owe money to whoever you have a judgment against. The garnishments really F up everything so if any money is owed, you will get paid.
This is CABL.com posting #282463. Tiny Link: cabl.co/mblD1