The allegation which the non Ahmadi Muslims try to state is that Ahmad(as) denied the coming of Gabriel on earth which is just another misrepresentation of the words of Ahmad(as) as we know Gabriel descends upon the ones who Allah blesses with divine revelation. Ahmad(as) stated:
‘Though he descends upon every person who is honoured with Divine revelation, the circle of the effect of his descent assumes small or great proportions according to different capacities.”(Tauzeeh Maram, Pages 67-68, Ruhani Khazain, Volume 3, Page 84)
Ahmad(as) did indeed believe in the descent of angels, although not in the manner that the ignorant Muslims of today. In fact Gabriel descended on him the same way it descended on Muhammad(saw) and the other prophets of Allah and other recipients of divine revelation.