I'm wondering if there is a way to be able to use the Gift Card functionality for omnichannel or in-store purchases? 

For example, if we wanted to allow a 3rd party to be able to update Gift Cards via the API, so a customer could use the Gift Card in their brick and mortar store, but the system was not on a POS using Magento, is that possible?

This would be the most ideal, but even a workaround solution could possibly work. 

Possibly a way to create orders using a guest account or "store" customer type that allowed the customer to purchase a variable priced item? Like a product called "in store purchase" and purchases simply bought that product and paid the correct amount?