Retrieving an existing order for payment with TNEW

Hello everybody,

I'm trying to understand the feasibility of creating an unpaid order for a customer in the Tessitura client, producing some kind of link to send to the customer, and allowing the customer to use that link to retrieve their unpaid order inside of a TNEW session so that they can pay the balance due on the payment page. All aspects of TNEW customization are on the table.

I am aware that TNEW supports completing a pending subscription/package renewal after logging in. I would intuit that this is only allowed because the possible order state that results from a package rollover is a constrained set of possibilities, and that there are plenty of possible order states that TNEW does not know how to render. I might hope that as long as an order is within the set of possible states that TNEW understands, that this should be possible by way of invoking an API endpoint to load the existing order into the current session. Interested to know if this has been accomplished before.

My likely alternative is to send Square invoices directly to the customers' emails, which would avoid TNEW login for the customer and any potential rough edges from this particular misuse of TNEW. But both of these would be new territory, so it's difficult to say which is the better option at this point. Any ideas or info would be appreciated.