Everyone can always use RCC, they are basicially just very advanced remote controls and as long as it's yours, you're always able to connect to it wirelessly, the only difference being, that non technomancers would need something like a commlink to communicate with it. As long as a character has acces to the Matrix he can can acces all his active devices that have Matrix Acces.
In order to control multiple Drones with a single action, they need to be slaved to the RCC(creating a PAN), which means the RCCs attribute get used. Which is good because it has better attributes than the Drones.(and you can boost em with programs)
You also can perform matrix/resonance actions while "using" the RCC, you don't connect/disconnect to it. It's no different then say: using a simple matrix action and firing you're gun in a single turn(AR obviously).
Just in case that is the confusing factor: You don't need to go into the matrix THROUGH the RCC in order to use it, as long as you can communicate with the RCC, you can give it ,and the drones connected to it, orders.