Amazon Investigating FBA Inventory

We offer two identical products on Amazon. One is FBA and has a fixed print and the other is FBM and has a customisable print. We made an error and sent a few units of the FBA product as the FBM sku, and a customer complained to amazon. Amazon Made initial contact with us and after an investigation into the FBA ski, appeared helpful and offered to move the inventory to the correct ASIN.

We have now given Amazon the correct ASIN but they have now replied stating that they are extending the investigation to all of our inventory. We list 150+ items via FBA and every item is security sealed so if they open one of every listing, that makes 150 items that we will have to request removal of because they will no longer be sellable.

Is there anything I can do to stop them doing this?