The problem, well one on the never ending friggin list - Is that the entire game is free.
There is absolutely zero incentive for sandbaggers and cheaters to, well, not. If you're that inclined then there's nothing stopping you here.
What might work in someway, maybe, is if there were a paid membership club.
Restricted to L100+ Tour Legends. You pay like say 500 credits per month. Those credits paid are used for purses. WGT would take something sure, so say like 80% goes to purses.
Tourney's and any game format is approved by the members, no more shitty RG's forced on players.
Players who are in the 'Club' can no longer play in the public tourney's or RG's or in anyway compete against the lowly regs. With the exception of the Virtual Tours of course. Hell that's easy enough to enforce, you simply would not be allowed to join off-limit matches.
AS and skins etc are still open, the restriction is on the public RG's and anything else WGT runs or will run. The public format games. I'm sure there's *** that I missed but you get the idea.
And for god sake at that level and with there being developed a community of 'Club' members - Take the deviation out of play. Golf clubs and balls don't have it in real life. And apply a neutral VEM profile to the status of 'club formatted level.'