procedure whereby all interested parties are invited to submit offers, the contract for each lot being awarded to the person offering the highest price, provided always that such price is at least equal to a set minimum price
... in the case of a sale by tender with no specified destination, where serious doubt exists as to the actual destination of the product, the release of the security shall be subject to proof that the product has been imported by a non-member country, unless lost en route as a result of force majeure.