Whilst through the film Rajeev Khandelwal and Tina Desai are assumed to be victims of Paresh Rawal's "tests", the climax of the film safely concludes they were the actual villains of the movie all the while.
Rajeev Khandelwal is an atheist in his real life. When Khan asks him before his third dare whether he believes in Khuda (God) or not, he immediately answers in the affirmative.
Bearing in mind the in depth details Paresh Rawal's character carries about Rajeev Khandelwal and Tina Desai throughout the movie and the amount of influence and resources at his disposal, it can be assumed that it was him who got Rajeev Khandelwal fired from his job prior to the film's events to make his scheme more authentic.
Rajeev Khandelwal initially was opposed of kissing Desae for one of their tasks, but eventually he complied.