NetSuite Inventory PO integration into Coupa?

We recently implemented Coupa for our AP solution and it is full integrated with NetSuite (POs are created in Coupa, invoices are processed in Coupa, invoices and payments sync to NetSuite). Generally, we're really happy with this arrangement, but we have some POs that we need to generate in NetSuite for practical reasons. We're trying to figure out the best way to manage these, because the POs can't be synced from NetSuite to Coupa, so right now we're doing a manual match to the invoice in Coupa and making tons of notes. It's a super manual process, and causes us a lot of stress and concern.

Our understanding is that Coupa's Inventory module isn't robust enough to map to NetSuite Inventory, so the solution that's been presented by our NetSuite consultants is to do a partial integration where the POs get moved from NetSuite into Coupa, but the PO creation and receiving is still done in NetSuite. Just wondering if there are any other NetSuite users who integrate with Coupa who can offer different solutions for POs that impact inventory.

tl/dr, We want to move NetSuite Inventory POs into Coupa but don't know how. Halp.