The league would not be able to come down on some owners.
1. They are not "technically" breaking the rules with arranged outside employment. Let's say that OwnerX has a variety of companies in his network and arranges for one of the distant ones to pay the wife or relative of a player to cover private education for their children - how would the NBL uncover that with their resources?
2. Piss off an owner, lose crucial sponsorship.
3. The owners methods will survive scrutiny anyway.
Best bet and very easy to quickly implement is to fix the points cap - won't solve all problems, but will help a lot, IMO. Don't allow a Saville to transfer his rating of 5. Don't use a statistical rating that will see someone like CJ Bruton downgraded just because he's on a stacked team while a Liam Rush goes up just because he played for a crap team.
Reduce the team points total in a climate where there is a whole new team added to the league, rather than increasing it (which has to rank as one of the stupidest things the NBL could've done).
Consider giving bonus points to bottom teams to help them in following years. Consider only allowing loyalty deductions to be transferred to non-playoff teams, etc.