First, we do not automatically pay affiliates their commission earnings; the merchant is responsible for paying out commission earnings to their own affiliates. Typically, you would pay these commissions as a monthly lump sum to each affiliate using PayPal, so the approach you propose wouldn't really automate a split of actual revenue funds.
Also, our affiliate system is not really intended to calculate revenue-sharing with a partner or supplier rather than a "sales rep" affiliate, and trying to set it up to approximate that is so tricky, and potentially unreliable if you have other affiliates, that really it would be far easier and more accurate to just use your Transaction Log to calculate monthly revenue for the relevant product(s):
You can go to Seller Admin > View/Download Transaction Log, select the relevant date range and product, then click View Log. You'll see a summary of NUMBER OF TRANSACTIONS, ITEMS SOLD, and total SALE AMOUNT for the selected product during that date range. Then you can simply calculate how much you should pay back to your partner/supplier for those sales of that product.