Exclusive AMA: Optimizing your Inventory Management with Shopify Experts!

We have custom templates using the Shopify Order Printer. However we are unable to access the inventory location via the app. We can access the inventory location if we use the default invoice and packing slips (not app, but built into Shopify). Why are there different fields/objects only available in the default invoice and packing slip, but not the Shopify owned and developed Order Printer app. Can this difference be reconciled?