You can argue, but you may just have to take it. Payment after completing a shop and reporting is contingent on having your report accepted by the client. If the client refuses to accept the report, the client will not pay the MSC for the report. If the MSC does not get paid, the IC does not get paid.
There is really no recourse to speak of. We are independent contractors and the MSCs are our customers. If our customers are not pleased with our work, we don't get paid. If the end user (the client) doesn't accept the report and pay for it, nobody gets paid: not the IC, the editor, or the scheduler. I'm guessing they will send another mystery shopper to re-shop the location.
You should edit your post and remove the client's name. Naming the client of Intelli is a violation of the ICA you signed with them and of our forum's rules.