Well, a transliteration/cultural explanation and waving the EU denied boarding rules cannot hurt if push comes to proverbial shove. Ticketed as Ibrahimov but passport name of Ibrahimoff doesn't cause issue there. Telling them that it is the same name and to pronounce it makes it more convincing.
Anyone have the IATA rules? [I'm sure this kind of issue comes up rather routinely across Eastern Europe, parts of Africa and much of Asia.]