Will Ferrell's SNL season finale does not include The Lonely Island?

Having seem Andy Samberg every week of SNL that I can remember this season I was surprised that Will Ferrell did not include him in the season finale. Am I reading into this too much or was Ferrell trying to keep it old school pre-TLI SNL?

The Lonely Island is three people, ya know.

As for Samberg, he was there in the last sketch (Goodbye Saigon) playing the piano. And Fred Armisen, Will Forte, Jason Sudeikis, and Kristen Wiig all post-date Will Ferrel and featured prominently in this episode.

The host does have some discretion about the direction of the show, but the decision on what material to include and cut ultimately rests with the writers and Lorne Michaels, and the big clock on the wall.