Two, really, with the third being under three in the Lack & Play.
Important point # 1: Yes, there is room in any Pop room - any onsite room, actually - for the Lack & Play.
More important point # 2: You cannot book a king bed room. It is not a booking category. You can merely request. Important point # 3: There are only about king bed rooms at Pop, and the majority of these are accessible rooms.
If this bed size is mandatory, king bed a booking category only at the Moderate resorts.