Hi dzined ,
We do not take any responsibility for the below action! Only for experienced users!
Please, remember to make a backup of your database before trying this!!!
Thank you for your question.
I know you are an experienced user, but we try to include this sort of disclaimer in technical posts, I trust you'll understand.
After the clarification:
Unfortunately, we don't have right now any function to get an Inventory by its location and sku, so you'll need first to get the product's inventories and check them all until you get the one you're searching for:
You can use the \AtumMultiInventory\Models\Inventory::get_product_inventories function.
After that, you can use the \AtumMultiInventory\Inc\Helpers::update_inventory_stock function to change the Inventory stock as you want.
Both are static functions, so you can access them anywhere.
Hope this helps.