though we're not dealing with the fbi so he could just keep half the disc
That's what you think
The FBI probably wouldn't find it if you cut the disc in half and kept one half. Half A can be thrown into a remote location such as the woods and Half B can be kept or thrown in a garbage can.
A data recovery expert could still recover partial information off of half a disc.
Just leave a pubic hair on it and nobody will ever touch it.