Not sure about Jambo House but the pool at Kidani Village at AKL didn't require your Magicband or room key to enter. It was just a gate that anyone could open. There was even an issue where I overheard a few guys that were bragging about being in the pool despite being Universal employees and NOT resort guests.
Also not WDW but I know Grand Californian in
Disneyland required your room key to open the door.