broker pays default mortgage???

[Aaron Walker]

My mortgage broker (in justification of why a loan is taking so long to go through underwriting) told me about a previous loan that he had worked where the buyer falsified his federal taxes. This taxes showed that he made 50k but he really was 30k in the hole. The "accountant" that signed off on his taxes turned out to be the guys brother. Anyways, he stopped making payments and our broker claims that he got stuck with paying the guys mortgage. How is this possible? I thought that he would want to give as many people loans as possible to collect a commission whether qualified or not. Its ultimately the banks/investors job to discriminate who they give a loan to.
Thanks