About all you can do is visually inspect the surfaces. Sometimes you might see an actual missing surface in some area. The problem is a problem with the model, not the toolpath. You might get away with leaving the model 'broken', if you simulate it and it looks ok, and shows no toolpath going through the model somewhere.
This type of error is often due to a construction problem, such as creating tiny sliver surfaces when extruding a part from an internal offset of a pre-existing good chain, or if the chain had bad trim to begin with, same thing.
It might also occur when a filleting operation has been performed too close to an existing edge, forcing the filletted surface to try to fill a zero width space at some point. Often, a different sequence of operations in constructing the model (filleting first, then trimming off some excess stock) can make a sound model.
If you post your file here, or register and post on OneCNC's forum (for more privacy), someone can take a look at the model....maybe find a fix for the model.