I see your point, but I think the fact that drones unequivocally exist makes it more likely that people will mistakenly attribute something they see but don't understand to them, not less.
Ultimately, I make no conclusions on this particular case; I merely state that I find it completely plausible that a large percentage of those 93 people were mistaken and caught up in mass hysteria, especially after reports have been in the media.
If 92 out of 93 witnesses were wrong that would mean that the strange drones were there to be correctly witnessed.
I agree that nothing is certain about this. I don't completely rule out the mass error or mass hysteria hypothesis either. I just think it's more likely that there were some drones behaving oddly in the area. I doubt the witnesses are exactly right, but I also be doubt they are completely wrong.
Ultimately, I make no conclusions on this particular case; I merely state that I find it completely plausible that a large percentage of those 93 people were mistaken and caught up in mass hysteria, especially after reports have been in the media.