I have been thinking about this deal all day. Man I feel bad for you!
I think if it were me, I wouldn't try to sell it even if I disclose what it was. I wouldn't want it in circulation. I don't know if your have an indoor set up but I would put it on that and use it for a training bike. I don't think I could sell it even if the party knows its fake then take the risk of it again being resold and the circle continues. I know its not on you if that happens.
The really sad thing is, the bike probably is a really nice ride if deemed safe. Its still nice looking too!