How to handle a situation

My husband and I applied for a mortgage and the broker asked for us to make payment arrangements with 2 collection accounts on his credit. One of the Collection accounts-Calvary Portfolio called us and we made an arragement based on what the broker told us to do. They stated they would send a letter in the mail out-lining the arragements but we never recieved it. Our loan went into underwriting and was shot back due to the credit score going 40 points under thier limit. We were shocked and realized that Calvary had reported us two days prior to going to underwriting on my husbands credit report thus causing the FICO score to drop. We have only spoken to them via phone and never recieved the letter for payment arragement. We have never even gotten a validation letter either from them. We need to regain 25 points to get back into the loan limit but cannot figure out how to anything. We disputed 3 medical bills that had been paid as well as a collection account but have to wait 30 days. If we pay the calvary portfolio collection will is help us out in obtaining the points back or what do we do.. I am at a loss and cannot afford an attorney at the moment. We currently have a mobile home mortgage-excellant standing and a car loan in excellant standing but that is all. 1 other collection account that was handled. Please help us!!