I don't see how it's a big risk when he has an undetermined value right now.
It's definitely a huge risk for a number of reasons...more bad than good can come out of this.
Physical limitations on full display, injury, turnovers...all of these can hurt his trade value for him.
It's better to just let him remain a mystery unless he comes in and tears it up. Not sure anyone sees that happening on a lame duck team
Besides GMs aren't fans. They'll look at multiple factors and if they liked Cousins coming out of college will look at the whole picture.
The whole picture is very small.
He was limited physically coming out of Michigan State. That's why he fell. There won't be much good to evaluate if he comes in and plays horribly.
It will be average at best.