My boyfriend and I already have our package booked and paid for. His parents just let me know this weekend that they would like to stay on site one night. So my question is this: If we are able to add them to our room would it mess up our free dining and everything? Our can they just stay in the room as it would only be for one night and they aren't getting the dining plan.
They can not be added to a room thats has a package . Everyone thats in the room has to have the same tickets and DDP (amount of Days.)
Now they could get their own room or when you get there sometime during your stay they may be able to add them for the day as a guest and just charge the $10 or $15 fee per person for that but that will totally be up to the CM you get.
We have never done that but from my understanding the answer would be no. In order for you to keep your free dining everyone on your hotel ressie has to have the same 'package' (i.e. tickets, ddp, etc.). You could try calling the resort to see what they say since it would only be one night. If you don't mind missing out on one night of ddp they might be able to do a split stay ressie.