I happened to be in AP Stats back in HS with the son of the owner of the business who certified all electronic casino games for the state of NJ. We took a field

I happened to be in AP Stats back in HS with the son of the owner of the business who certified all electronic casino games for the state of NJ. We took a field trip to the business and his dad gave us all a tour and explained all of the testing they do for this sort of stuff, the code reviews, making sure the machine's odds were actually what they said they were etc. I don't remember many details at this point (it was 12 years ago, which is insane), but I do distinctly remember the scale and just the amount of stuff they did. It's very serious business, because it was in both the casino owners and NJ's interest to make sure the machines were in fact not hackable as much as possible.