not sure if this helps, but I had my steering wheel off the other day, and looks identical to yours. Disconnect battery (-'ve terminal), have a cuppa whilst the electrical systems discharge. Then key in ignition lock to prevent steering wheel locking, rotate steering wheel to expose where the black hooks are on the back of the airbag. Push on the airbag/horn, and with flat bladed screwdriver, prise the spring from under the black plastic airbag hook at the back of the steering wheel, and repeat twice (there are three airbag hooks, steering wheel needs to be rotated to expose each in turn).
Airbag will then be free, disconnect wires, then access to radio buttons etc is straightforward.
CAUTION: Do not do what I did, and spin steering wheel left several times, then right several times. It will rip the clock spring, and that cost me £106 from main dealer...if you need a video, message me, I'll try and oblige.