In fact, all the orientalists have inherited this allegation from medieval times when there were no such scholars as orientalists. Only a very ignorant class of church fathers criticized Islam as they thought fit. And it’s the ugliest criticism of Islam because it’s based on no foundation, only on stories and things.
So they have this present generation, although it has softened down some in its attitude, but not entirely. Anyway, it has inherited all the criticism from that generation. As far as the Ahmadiyya point of view is concerned, you better read a chapter on slavery by Hazrat Mirza Bashir Ahmad Sahib in his book Khataman Nabiyeen. The best handling of that question so far I have read is in that chapter of Khataman Nabiyeen.
So if it’s available, that can be translated and republished in review. Note it down. This is an issue which is agitating the minds of the West and it should be given full treatment.