I've seen the like attempted before. The Catholic is the first to give up, while the Protestants tell each other that they're wrong by mostly quoting.
most "christian" groups don't exactly believe the same thing anyways.
It would be amusing to lock a Catholic, Baptist, Mormon, Jehovas Witness and someone from the church of god in the same room to discuss theology.
These prophecies are so entertaining by the way. If there is a hell, these "prophets" will surely be the ones roasting for exploiting the idiocy of the ignorant.