They've never said something is allowed either.
I knew someone who bent over backwards to try and get a Linden, the one responsible for the blog post about the ban, to come and look at his system and say whether or not it was against the rules. Bent over backwards, invited him over, sent him a copy, the Linden wouldn't teleport or accept the item, said he wouldn't render whether or not something was within their guidelines until after it was AR'd, and even then he would only find out arbitrarily. This was the policy maker, the head of the department, who said no, I won't render the legality or acceptability of any system in
SL.
At best Z-Fuck got some random CSR liaison who works out of their house for minimum wage with LL to say "Oh yeah, this is fine!" but nobody who decided policy said so, and sooner or later Arbitrary Linden will delete his shit. Which serves him right for skirting semantics to advertise his systems.
At worst, this is all a complete lie, and you should be ass fucked with a cactus and then get your shit deleted.
And good riddance, because I don't care about gambling, I care about scammy fucks that ruin sims with their shit. Any sort of updating system is going to lag, it's NOT POSSIBLE to make a game in
SL and say "Look, we're low-lag!" Coupled with the pathetic behavior that seems to attract people to that sort of income-gatherer and it's a recipe for mouth breathers.