Yes Garfield, not "I hope I don't die", but "I hope you brought a snack."
Panel One: We already know what Dr. Wilson's receptionist, Nel, looks like, so why not show her? A) her appearance was just a punchline sight gag about how ugly she is, and seeing her in this context might be distracting. B) the panel's a little crowded for Garfield as it is. C) it's easier not to deal with people's reactions to seeing a cat walk on its hind legs.
Panel Two: It's an unfair complaint to criticize comics reality which I always allow to warp reality to best tell a joke. The zoom-in reveal places the skeleton closer to Garfield than it could have been in panel one, but that's totally okay. Not-okay is that the skeleton - smaller than Garfield, and without a tail - seems to be that of a baby hippo.
Panel Three: I'd like to think Garfield doesn't think a mere snack can save him, and has just accepted that the waiting room shall be his death chamber. He would've asked for a snack anyway.