There are adjoining rooms in the Sequoia, as there is in the Cheyenne.
I think the main differences are
Breakfast: same items, but Sequoia has individual yoghurts and fresh fruit salad not from a tin. You are shown to your seat, but it can still be busy. If you stay anywhere but the lodges, you don't need to leave the warmth to go to eat.
Pool: The Cheyenne doesn't have one. But if you are not worried, save your money and stay here ;-)
The bars: BOTH have fires lit in colder months, though the Sequoia is central in the bar. The Cheyenne drinks are slightly cheaper than the Sequoia.
Decor: Sequoia is fresh and the rooms are bigger, though the Cheyenne is still ok and the bathrooms have separate heating in them and it's boiling in Winter!
Air con: The Sequoia has a/c and it controllable via unit on the wall. It works brilliantly. Cheyenne has electric fires which are really warm in Winter. The ceiling fan is a little noisy and the person on the top bunk will get a good breeze, but remember it's just circulating the same air.