At the end of the movie there are fake credits for the movie, crediting Donald J. Trump for almost every task (exceptions are e.g. "Catering - The Mexicans"). During these credits Donald Trump is talking to the audience. After that the real credits for the movie appear. After these credits Ron Howard appears and says how awful the movie was and he wants all to forget that this movie or even Donald Trump exists.
At the end of the movie the following credit appears:
Some of the characters appearing in this fake TV Movie may be based on real people, but we took huge liberties and basically made a bunch of stuff up for laughs. With the exception of Alf. He is not real. He is a puppet, and Melmac is not a real planet. And if Melmac was real, it doesn't exist anymore because it exploded. Anyway, even if Alf really lived, he probably wouldn't have been Donald Trump's best man as the filmmakers don't think they would have been that close. May be would have been an user at the wedding or the DJ at the reception? Doesn't matter.