The relationship between UK and Holland is complicated:
A VAT-registered UK business importing goods ( read training) from the Netherlands should give the Dutch supplier its UK VAT registration number (including the GB prefix) so that Dutch BTW does not get charged. If BTW is charged, the UK business cannot reclaim it on their UK VAT return or by a direct claim to the Dutch tax authorities. The best that the UK business can do in these circumstances is to confirm its VAT registration number to the Dutch supplier, then ask for a full credit note and for the goods to be re-invoiced without BTW.
Best option, forget it and concentrate on being a pilot not an accountant!