I imagine a scene where they have a rastafarian gardener.
Kids: Pointing at him saying look it's an alien.
Gardener: Hey maannn, it's me maaaan, the gardener maaan. I'm looking after the grounds maann. The earth needs to be looked after maaan .
Kids: The alien is communicating with us and wants us to look after the earth
And thus the legend began
The alien in Predator did have dreadlocks so maybe half of the kids were describing the traditional gray alien and the others had been influenced by a more Predator type alien.