In a similar case we contacted the MSB hotline to determine an answer. We have a pawn shop that allows people to use payroll, gov't, etc types of checks to make payments to the pawn shop for their loans and receive the rest back in cash.
According to a nice lady on the hotline, if the pawn shop returned a portion of the check in excess of $1,000, then to her knowledge it qualified as an MSB in practice.
_________________________
In order to discover who you are, first learn who everybody else is. You're what's left. -A Fortune Cookie