Can we setup accrual offers for vendors (not customers)?

Here is the scenario:

We have a Distributor that buys our products and sells them to a 3rd party. The 3rd party has negotiated a $2.00 billback with our company. But because they never buy from us directly, they are not setup as a customer. They only exists as vendors and receive checks for whatever their total billback amount is.

I would like to be able to use IDSM functionality to create the accruals but since my 3rd party is not in the customer master, I can't set them up as a beneficiary for the offer and create a claim for them.