Yup, but I think the agreement may have been for Trump to do what he does — make lots of noise, beat the media at their own game, and take the heat — and then join Cruz as the VP so that he can really learn how the fedgov works. Thus: 8 years Cruz/Trump followed by 8 years Trump/? (Palin?)
Trump knows how the government works; he buys it daily for his own benefit, like any wealthy liberal Democrat.