At least one poster paid the upcharge for the shusi and was very happy with their meal. Bicker is right, this restaurant has restrictions.
Teppanyaki isn't willing to give away the store to MYW Dining guests. Either be prepared for the restrictions, be willing to pay extra or go to one of the many other restaurants that have very few restrictions.
Lobster is not included, you really have to check when you get to WDW and see what the current policy is.