Of course, if Christians had been breeding horses and mules together, I'm not sure why a human-ape hybrid would cause more doubt. And during the Middle Ages, it was commonly believed that women who gave birth to deformed and mentally challenged infants had slept with animals. There are several famous "calf-people" and "sheep people" from the history of England, who usually came to tragic ends at the hands of their ignorant peers. It seems like the question of whether a humanzee would be significant to anyone's religion would rely more on the particular theological interpretation given to the hybrid.
Fortunately, none of the inseminations produced a child, and attempts to find a human female volunteer willing to carry a humanzee child to term also came to naught. The entire experiment has the stench of Leninism, the notion that individual humans (or humanzees) are just interchangeable parts who may be sacrificed for the greater good of International Socialism. Considering that it would only be a few years later that the entire Soviet Union would be forced to reject genetics in favour of the worthless Lamarkianism of Lysenko, it's only surprising that the entire episode hasn't been erased from history.
The reason why Arthur Jermyn’s charred fragments were not collected and buried lies in what was found afterward, principally the thing in the box. The stuffed goddess was a nauseous sight, withered and eaten away, but it was clearly a mummified white ape of some unknown species, less hairy than any recorded variety, and infinitely nearer mankind—quite shockingly so. Detailed description would be rather unpleasant, but two salient particulars must be told, for they fit in revoltingly with certain notes of Sir Wade Jermyn’s African expeditions and with the Congolese legends of the white god and the ape-princess. The two particulars in question are these: the arms on the golden locket about the creature’s neck were the Jermyn arms, and the jocose suggestion of M. Verhaeren about certain resemblance as connected with the shrivelled face applied with vivid, ghastly, and unnatural horror to none other than the sensitive Arthur Jermyn, great-great-great-grandson of Sir Wade Jermyn and an unknown wife. Members of the Royal Anthropological Institute burned the thing and threw the locket into a well, and some of them do not admit that Arthur Jermyn ever existed.