The original post asked about a SAR for mortgage fraud and nothing that has been stated indicates that loan fraud might be occurring. Public assistance fraud/hiding asssets is another story.
I read the OP as a Customer applied for a loan and the loan application contained a fraudulent or inaccurate statement regarding the purpose of the loan. Subsequent discussions with the customer revealed that the customer suggested that they were trying to hide assets to qualify for medicaid. If this understanding is accurate, I stand by my original comments.
If I'm mistaken in my understanding of the events, then a perhaps a SAR is not justified.