They catered to my fiances peanut allergy although I know that is not quite the same. You could always give them a call. They offer dining room seating as well if the Hibachi grill makes you nervous.
I would recommend you call their corporate number and enquire if their stores use tree nuts in the dishes. As they are a chain if one does it they all do and its usually regulated via the corporate offices
I wouldn't eat off the grill with an allergy like that, but she could eat a prepared meal from the kitchen and sit with you at the grill. Just be sure to inform them of her allergy so they take the appropriate precautions!
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