While I do not have a solution, I want to confirm with you that your findings are correct.
So when you submit a price to The Netherlands, then regardless of location, for example the US, the price must be what is submitted in Google Merchant Center. IE VAT inclusive.
The solution is to only exclude VAT, when the customer enters a delivery address or payment address outside the US. This means, you should not change the address prior to knowing where it is going.
Meaning in the checkout when the details are entered, not prior.