Tip prompt doesn't show up on POS when checking out Online Orders

Currently, for some reason, Shopify doesn’t allow the tip prompt to show up the Shopify POS for customers when we check out customers from online web orders.

For context, we take online orders through our website, but the order payment status is “payment pending” or “partially paid” since we take a deposit for their service. Customers come into the wellness clinic, have their treatment and then we check them out for their remaining balance on the POS.

When we check the customer out from their online order, we are able to pull up their online order on the POS and check them out for their balance, however, the tip prompt is alwaskipped. I’ve gone back and forth with Shopify support and they said the following: "Our Technical team has determined that tips cannot be applied to an Online Order or POS Order that is “Marked as Unpaid or Payment Pending”

Wondered if anyone else has had this experience or has a good workaround for being able to check customers out on the POS from an online order or payment pending and have the tip prompt come up?

Thanks!