Your explanation was a little foggy, but if I understand it, you want to depict a panzer crew bailing out and retreating, while a Panther, halftrack and infantry are advancing. Is this correct?
Having a panzer crew bailing out and retreating with reinforcements coming up is a good dio idea. The possibilities of creating a sense of drama and urgency would be easy to do with such a scene.
It is important though to make sure your dio puts the emphasis where you want it; on the advancing troops OR on the retreating, battle-weary troops. Otherwise the scene will be confused and not make sense to viewers. Shepherd Paine's book "How to Build Dioramas" is an excellent source and has helped me immensely with composing, laying out and building my dioramas/vignettes. It helped me understand the balance and flow of the diorama idea, and how to make it better!
Start buying the kits, building 'em and keep developing that idea! Keep us posted!