I think I've seen that picture before, or at least other similar ones.
I do think it's very possible humans were around when dinosaurs were, however.. A centaur is like something out of science fiction or fantasy... Then again... Maybe I'm wrong... Maybe there are some historical accounts similar to like dragons and stuff? I dunno. It is interesting to think about though.
And yes. I agree with you. Current times are quite warped, so in some ways it's even more difficult to decipher what happened long ago!