Arriving from LAX on my way to Kathmandu (with Emirates and FlyDubai), I will arrive at Terminal 3, and depart from Terminal 2. I am planning to spend the long layover at the Terminal 3 airport hotel; if my departure flight is from Terminal 2, am I allowed to stay at the Terminal 3 hotel, and then go to my gate in Terminal 2 once the departure time comes? Am I allowed to use that hotel if my arrival and departure terminals are different?
There is an airside transit bus from T3 Concourse A apron level, that goes to T2. So you can stay in the hotel in T3 and then use the bus to transfer to your next flight.
If you find you are not in Concourse A, there are also airside buses that will take you to Concourse A.
Ask any Emirates or airport staff for directions if you need to do so.