Honestly, without the rpgm type I would've said Princess Colosseum would fit. Villainess Quest 2 had me think the Red Ranger AI game, which had a casino quest, but the casino thing is so common that more information is kinda needed.
I could also point towards Temptation Colosseum by DryGame, it has a casino scene and stuff that I think is optional but the style is not even close to Princess Honey Trap.
Another newer game with a casino sequence was Avarice Dungeon, but that was not the classical rpgm game.