Could be wrong to an extent, but I am sure that the problem is when you installed the wide angle extension, the additional glass elements on the extension caused the light to bend and slow down way more than what the cameras triple sensor prizm split is calibrated for. This is one of the things that a single sensor has on the triple sensor set up, the chroma sampling is WAY better than any bayer could ever be, BUT, the calibrations and measurements for the lense elements are MUCH more sensative. And yes, they can be thrown off, just a single drop to the ground from waste height can ruin a prizm set up, or any other camera's sensor alignment for that matter.
