Marketplace discounts not applying to consumption

We have a partner who's loaded Marketplace private offers, however the private offer discount is not being applied to the monthly consumption.  The customer is being billed at the full SKU rate without any field to update which allows the discount to apply to the consumption line.  

We've opened a support ticket which has gone stale without help for weeks and no engineer assigned.  Customers are ready to walk away from Marketplace because billing issues cannot be resolve.