You say distinguished i say well-known eminent 

Like i said above it seems fair to remove well-known, because perhaps he is mostly well-known to iranians and Iranologists. But if you still insist that he is not emiment either, and it seems that you have prepared a list of words to choose, i really don't see any reason for changing eminent, because he is in fact an eminent iranologist.
However if you still insist then you might as well for example call pakistan's president not known at all or englands queen an old woman. Now you do understand what i am saying, right zora?