Dispute not beinh attended

I have logged a dispute with Expirian and I was not attended fairly. I paid up this certain account through the Debt Collectors. And i requested the Debt Collector's to update that the account has been paid up on Itc record, unfortunately the Debt collector informed me that the creditor that i initially borrowed a loan from is not existing anymore and as Debt Collectors, they do not have a system of updating on Credit Bureau. Instead they provided me with a paid up letter and referred me to Expirian by an email to Dispute so that my account can be updated as paid off. I have tried to log the dispute with Expirian, they are refusing to assist me claiming that the letter is not more 60 days. They are giving the creditor a chance to update. But i have an email from the Debt Collectors referring to Expirian, declaring that they don't have a system of updating as the initial Creditor is not operating anymore. Now i am forced to wait for 60 days giving a chance a Creditor to update. And Creditor have made it clear that it will not update any given time. I have sent several emails attaching all relevant documents(paid up letyer, proof of Residence, id copy, and referral email from Debt Collectors) but Expirian is still refusing to assist me. What a bad service I am receiving from Expirian. Why must I wait for 60 days even if the Debt Collector habe confirmed that they will not update the account and referred me to Expirian to assist.