It's clearly not Boyz II Men when you listen to the voices. It is a great song though. Maybe Nate, Shawn and Wan should consider recording it. It would definately appeal to their audience.
The music is straight out of nights and you could play as sonic as a secret character in either Christmas Nights or Nights (I forget which). I say this is a fake!
Shawn, "Dreams" is my most favourite Boyz II Men song. It would be amazing if you performed it in the UK. Another classic is "Luv N U".
Peace!