No excuse for not being aware of MSA or local procedures. Even if it was their first trip across the pond, you'd think that their company would have a briefing sheet for Europe and the North Atlantic that they would read. I'll guarantee that they've sat through a Simcom, FSI or CAE International Procedures course. If they'd have listened, maybe this wouldn't have happened.
My recollection is that the FAA mandated the completion of an international procedures course before pilots involved in commercial operations could fly internationally; is that not the case for part 135?