Though it is revealed at the poker game that Stan has never killed anyone, he had already killed three people in episodes that aired prior to this one. He accidentally killed an artist in "When a Stan Loves a Woman" (by firing in the air) and a coworker in "I Can't Stan You" (by vaporizing him, in a fight over equipment he thought was a penis enlarger). He additionally killed Jay Leno, in anger, in "Stan of Arabia: part 1".
At the beginning of the poker game, Roger throws down his 2 cards face up, then they are never seen again.