Hey there,
last year i’ve got the same problem, and i think the problem is not the rudder… Are you request the pushback by the fly pad? If so make sure to relise the tug before taxiing to the runway. Sometime the tug will not spawn and many pepole think is alredy gone, but is still connect do the plane. Just try to relise the tug, if you do that, it should turn.
Video in my topic here:
If you still having the problem, contact the FBW dev.
Sincerely,
Filippo