Ability to mark a Toast order as "Claimed" via API

Hello.  I am working with a two way tab sync with Toast.  We allow users to add to and pay for Toast tabs through our application via the API.  We are running into one issue, however, and are hoping somebody can provide some guidance.  When we start an order in our application and then start it in Toast, it has our dining option and thus is obvious to the server that we started the server and will collect payment from the guest if they don't manually close out the order.  When an order is started in Toast, we can allow a guest to add to it, but since we cannot edit the dining option there is no way to make it obvious that a guest has “claimed” the order through our application.  This leads to server not knowing whether we will collect payment or not, and whether they should be worried about walk out or not.  

Is anybody able to provide suggestions as to how we could accomplish our goal of making it obvious that Toast orders have been “claimed” in our application so that the server knows we are able to collect payment if the guest leaves before closing out?  Some teammates have suggested things like injecting a dummy promo, or payment, but it feels like those are hacky solutions that could lead to other problems.