Token's security guard won't let you in to see him.
|Don't gaze at it too long!
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Get a gas mask from Jimbo's Guns and stop the security guard from pepper spraying you. Defeat him and recruit Token's help.
Go left from the gate to Token's house to Jimbo's store and buy a gas mask from him. The pepper spray won't work and the guard will panic and attack. Defeat him and you can go to Token's door. Activate it and he will come out. After you give him the letter, he gets dressed and heads for Cartman's house.