There are so few "exclusions" that it's hard to remember them. What have you read is excluded?
Here's what I can remember is excluded:
The Kitchen Sink dessert at Beaches & Cream
Pizzas larger than individual size at Via Napoli
For awhile, sushi was excluded as an appetizer at Teppan Edo, have seen that it may no longer be excluded
DDP and DXDDP does not cover the separate sushi menu at Tokyo Dining
Some restaurants will require 2 persons to order items labeled "for 2"
Drinks in souvenir cups or accompanied by glowing novelties are excluded
Alcoholic beverages are excluded everywhere except the dinner shows
Some restaurants may exclude certain "specialty" non-alcoholic beverages
California Grill excludes the two most expensive sushi dishes as appetizers, although they may be ordered as entrees
Flying Fish's prix fixe menu is not included with DDP (on DXDDP you can order three courses anyway)
Special dining experiences (like Lunch with an Imagineer, Lunch with an Animal Specialist, Flying Fish Chef's Counter, etc) are not available on DDP or DXDDP.
I am not sure you would get any useful information by calling the restaurant, and it is more than likely you would get none from WDW-DINE.