Sorry I missed this post until now.
I don’t think this is anything hardware-related to I’ve moved this thread to a more appropriate sub-forum.
However, it’s possible the nose wheel steering isn’t armed, it needs hydraulic pressure to function. Secondly, it’s possible it won’t arm due to the wheel angle, in which case use differential braking or BetterPushback to realign the nose wheel so it’s straight. You should then be able to use the twist grip yaw to steer.