Again, not MD-11 specific, but I can't conceive of using the movement of the yoke to indicate flap/slat motion - that's what the flap lever and the flight controls page are for!
The explanation of slightly asymmetric flap/slat motion - or even slight asymmetry in the rigged positions - is by far the most likely. If the yoke is moving, then the ailerons are certainly being deployed (unless the control system has a fault!)