“Trust” is why you should test your raws. Right now you are trusting your business to your supplier. It’s cool that you test your finished products, but think of how stuck you’d be if you brewed everything up and it all came back low-dosed. You’d be out that time and you’d have no inventory.
Brew your products and keep track of the inventory. As you hit half-out, get your next batch of raws tested. You can easily figure out a product rotation so that you’re not waiting on anything forever.
If your supplier messes up, you’re fucked. You know how that would mess up your reputation in this business. Testing raws protects you more than anyone else.