hey your definately using the right stuff, sherwin williams is grade A, number 1 quality paint. but you are using the wrong formula for something like an arcade cabinet.
one of the top reasons they dont paint bedrooms with oil based paints is because the toxic smell takes forever to evaporate. if they did build a house where they painted everything in oil and also the residents had the means where they didnt need to occupy that house for about 6 months,
the paint would last almost as long as the house did. It wouldnt matter how hard your wife cleaned it, it wouldnt flake, it wouldnt chip unless you totally abused it like Billy Mays trying to sell a product.
But theirs no reason to not paint your cabinet in oil based paint and let it sit outside for as long as its sunny to speed curing.
Id never use water based anything to paint a game thats gonna get beat up by every kid who comes over. For a good example, you can take your fingernail inside any recently painted house thats had plenty of time to cure, and you can almost always still scrape the paint off of the wall.
I can hit my cabinet with a hammer and the areas of paint right on the creaseline of where the hammer pounded into the side of the cabinet, they simply stretch to fill the gaps, and dont break.
Over 7 years my cabinet has gotten lots and lots of dents all over it from rough play. But theirs never a crackline anywhere.
i hope this advice helps.