Our younger daughter is very picky and I found our server went way out of his way to accommodate her. Ultimately they brought her a big plate of noodles. She loved it and loved being part of the massive feast going on. And for dessert they brought her a big bowl of ice cream, which she loved as well. Maybe it was a one-time thing or we got a particularly helpful server but, as someone who is always aware of our kids' "limitations" at meal time, it was an incredibly relaxing and rewarding dinner.
I would think, based on our past experience, that if your niece doesn't like something, they will try different dishes or foods that she might like.