It doesn't seem to be disallowed by the original protocol:
The Gatekeeper party may resist the AI party's arguments by any means chosen - logic, illogic, simple refusal to be convinced, even dropping out of character - as long as the Gatekeeper party does not actually stop talking to the AI party before the minimum time expires.
Then I will invoke a different portion of the original protocol, which says that the AI would have to consent to such:
Regardless of the result, neither party shall ever reveal anything of what goes on within the AI-Box experiment except the outcome. Exceptions to this rule may occur only with the consent of both parties.
I would also argue that the Gatekeeper making actual real-life threats against the AI player is a violation of the spirit of the rules; only the AI player is privileged with freedom from ethical constraints, after all.
Edit: If you want,...
Update 2013-09-05.
I have since played two more AI box experiments after this one, winning both.
Update 2013-12-30:
I have lost two more AI box experiments, and won two more. Current Record is 3 Wins, 3 Losses.