I'd call GEMB again and explain what happened as ask for removal again. In the future, do not send a letter to the CRAs. Leave the CRA out of it; only send a copy of that letter if the lates weren't removed within 30-45 days.
Per the medical lender, you can use a copy of GEMB's letter for the loan process. Under a manual review the lender won't take those lates into consideration.