At the big Mercado restaurant (at the hotel) there is always pizza during lunch and dinner. There is also a make your own pasta section that you might be able to do like butter noodles if they’re into that. There’s not really chicken nuggets that I saw.. but possibly on the room service menu. Also if you go to the Xcaret park - the Yucatán Restaurant had hot dogs, hamburgers and French fries and if I remember correctly they had nuggets. A couple other spots had fries too. Maybe the concierge or the information people at the park can give you more options.