Yes - it's my observation that they do indeed dream.
I've often seen my beardies, bluetongues and when I had water skinks, twitch their legs , move their mouths like eating, and even sometimes wake up with start and acting like scared (by what they dreamt, this in particular the water skinks who were all rescues and originally wild and exposed to seeing scarying things (cats, dogs etc) and even scary things happen (cat attacks on other lizards).