So you do not know source of cash, the activity in questioned did not go through your bank, and you are not alleging that the borrower is lying to you about business income as he is not stating more than his returns show thus no mortgage fraud? What is the activity or crime that is coming through your bank?
I know you are looking at possible tax evasion and that is a valid concern, but without even asking the guy about the source of cash, I dunno if you have enough to warrant that reporting. Your call.
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