Hi umarsear
I know the location is not stored against the inventory. I am trying to get back the location associated with the product. Whether it is with multi-inventory or not does not matter. I am passing a valid product id and getting nothing back when a location is assigned to that product.
It matters. If a product has Multi-Inventory activated, it has no locations, If you inspect the product page, you'll see that the locations meta box is missing there.
This is because the locations are handled at the inventory level for them.
For the rest of the products with MI disabled, you can use that function and you should receive the list of terms. This has nothing to do with ATUM as it's a WP built-in function and ATUM Locations is just a custom taxonomy.
I hope this helps.
Best Regards,
Salva.