I don’t have the toon T-Rex, but you probably need to seelct the head and look at the morph list for it. Which application are you using? In DAZ Studio 4 you probably need to use the Parameters pane to see the morphs, and if it’s an old product they may appear in the Genreal section rather than having a neat Morphs group.
What is Mimic ?
.
Mimic is a Lip-sync program, and also available as a Plug-in for Daz Studio and Carrara.
it takes a vocal clip of audio, and creates the animation for the figures mouth and head