I watched the episode, and I didn't realize that was him until I saw his name on the credits. Then I recognized him immediately. I had only seen him in La Cage so I didn't recognize him as a man.
Dean: Can I tell you something?
Lorraine: That depends on what it is.
Dean: I think you're really really pretty.
Lorraine: (after a pause) Ok, you can tell me that.
Also, NBC is owned by Universal Pictures, which produced and released MAMMA MIA!: The Movie as well as the film's DVD incarnation.
NOTE: Last night's episode was titled MAMMA MIA and the TV spot/commercial during the end credits for the new lower-priced DVD of the film was fully intentional.