That would be a no. Tree frogs, especially the red eyes, need quite a bit more humidity than cresteds do. (This was what I was told when I asked the same thing, about frogs and cresteds
) I have heard though, that you can house pink-tongued skinks with them if you wanted to mix species. I have never actually seen one of those guys before, and they arent very cheap. But i think the Rhac book says that they can be housed together. Hope this helps! And I am no expert on cresties, i got my first one back in september, so feel free to correct me if i am wrong, anyone 
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~Melissa~
1.3 Leopard geckos (Guido, Oasis, Gypsy, Marli)
1.0 Bearded dragon (Pharoah)
1.0 Hog Island Boa (Michelangelo)
0.0.1 Crested Gecko (Picasso)
1.0 Ferret (da Vinci)
0.1 Chinchilla (Eevie)
And Jack the cat!
Melissas Menagerie