My proposal is that, when we do get an article on him, it should be "Imre Aladar", with a note of some kind on the original name. Considering the info you bring in, he probably made an even more radical change in using the Romanian version (for lack of a better word) of his name: I double checked, and the 1978 dictionary has him under "A" (I'm guessing that, aside from not using diacritics, he inverted his names?).