Yep... If they were real, the Predators would win, but if it is for the movie, they always have to make the stronger force fall under a weak force. I know this happened in the past with the Hannible. Holding off against a large Roman army with his few troops, or so I've read...
But seirously, for the movie making industry, they would do anything to take the crowds' attention and prove to Predator fans that the Xenos can kill all those big hulking monsters who is stronger. I'm neither a Xeno or a Yautja supporter but if I see something that is like a one lone Predalien in a Predator Mothership, I favor the Predators, but if it is a lone Predator in a Hive, then I have to favor the Xenos.
Look around each corner before you move because the chances are, you are not gonna make it.