This fixed game selling is legit and really happening.
Fixed games are cheating in itself so how could the selling of fixed games information could be legit.
Do you have any source where you see this is been done on large public scale and also been legit ? I think it might happen for few matches and also at a limited scale. If any player is caught in fixed match, it would be end of career for him.
There are actually more matches then most of the people could imagine, the clients I work with would have at least 1 match per week.
There are some leagues even designed for fixing, this especially happening in some Russian small leagues.
But you're correct, those organisers don't normally share their info with public, because in this business they normally work on spread market.
If they share the info with public, not only the spread will move to fast to cause the bookies to suspend the market, but those who bet on the match, their account will also get suspended.
In this case everyone lose their money, not even to mention earn any money.