Culprit #1: The Sheiff
Reason: He built the robots so tough, that his rescues would be allowed. But after Cool Steel attacked two guests, he turned them off. But when someone started medding round his lab, he turn Cool Steel back on.
Culprit #2: Gibby
Reason: To figure out how the Sheiff built his robots so he can build a theme park to impress Velma Dinkey.