I'm just guessing here, but I think a lot of European companies that do international business, use English for their products. Plus, Vic makes SAKs for more than just their Army contract, so the parts would be made for all their knives, and so any instructions stamped into those parts would be in English, and the instruction pages would have translations for any other languages.
I've had similar questions about the English stampings on my Swedish-made Mora knives; this is the best explanation I've come up with.
Matt in Tx