As mentioned before - cheating with players happens in public, with plenty possible watchers taking care and intervening via Cheating Ticket.
There´s an activity low at the end of each season concerning users who are currently not involved in the playoffs, so the amount of "real" monitoring of what goes on with draft picks comes down to maybe a handful coaches at best per league. That´s VERY few people to realize shady moves.
Zwei Dinge sind unendlich, die Dummheit und das All...