According to the time table for the rock art, pictures of camels/dromedaries are among the youngest. Which make sense as the use of these animals became more useful as the climate became drier.
Many of these pictures are pretty primitive, and one actually shows a dromedary being used by people.
I found only one picture of a camel (two humps) together with a dromedary.
It looks to me as the quality of the pictures was not as good as earlier.