Again...there's really no definitive answer to that because Fredo's exact 'role' is simply not addressed in the movie. All we hear him telling Michael later on is that he was promised 'something in it for him' if he 'helped with negotiations'. He did not specify how he was asked to help, what he did, or who (other than Ola) he spoke to.

We realize he did SOMETHING to enable the assasination attempt on Michael - but if you put into perspective Fredo's character I just cannot picture the guy physically entering his brother's bedroom and opening the drapes not realizing there was going to be a hit.

So if you believe both his statements to Ola that he was lied to...and to Michael that he didn't know it was going to be a hit...then it cannot be possible that Fredo opened the drapes. Even a kidnapping plot that plaw brought up Friday - I don't think Fredo would've gone along with anything he thought would bring physical harm to his brother. In his innocent stupidity whatever he did or whomever he had contact with...he thought he was helping with negotiations, as he said. Make no mistake though, it was STILL a betrayal because he knew he was doing something behind Michael's back that was related to business.

But unused (aka useless) scripts aside...there is nowhere in the film that we are told what he did. It's all up to speculation or even better who CARES what he did, whatever it was allowed the film to go on ....

Apple