Awesome to hear!
Just for an example, I think it was RTD's website that I was ordering things on that had sort of the same restrictions. It would let you put them in the cart, then when you went to check out, it said certain items (
batteries of all things in this case) in your cart couldn't ship to Canada, and highlighted them. Just removed them and it worked.
Maybe you can chat with him and see how he did it?