He does make a crack at it in the preview. Says don't make it green or animated when he is on the stretcher.
According to Tim Miller there were more than what you see in trailer. There was a scene they shot with Colossus:
“We shot a few more Green Lantern jokes, but I’m not sure how many will survive the cut. Ryan definitely had some Green Lantern issues to work out. We had about a minute’s worth of dialogue between him and Colossus where he talks about it, like, ‘So a guy comes with a thousand-dollar suit and says, ‘We want you to play a superhero,’ but there’s no script yet and the release date is completely unmakeable…’ He goes on this whole anti-Green Lantern run, but I’m not sure it’ll stay in, because probably not even half the people in the theatres will get those jokes…that scene’s one for the DVD extras, for sure.”
http://screenrant.com/deadpool-ryan-reynolds-green-lantern-issues/