We travel with a Golden Retriever and she has the back seat of the CC with the seat folded down. She travels very well.
Since you are planning, here are other things to think about - will your animals be OK when you have to leave them at the campsite? Will the 5er or TT get too hot while you are away? Will the dogs bark excessively? Are the animals good around people? Many campsites will not tolerate misbehaving animals.
Our dog is trained as a service dog and is very well mannered. When we leave we can usually take her along but when we are unable - the two air conditioners are on and the Maxifan is running on low. If power goes out the 5er will generally stay cool enough for a few hours, especially if we have a shady spot. Otherwise we simply can't be gone very long.
Hope that helps.