Please have a look at the image. Hope it explains the problem understandable.
I’d recommend using the DragDot stroke type. Start your stroke on a part of the model to the side somewhere, then drag the dot into the gap.
It’s important to note that this will only work if the original lines were drawn in the same Drop as the hole fill. This is because when you drop the model, PM remembers the current depth and builds onto that. New strokes don’t overlap. Once you pick up and drop again, that new state is what’s stored. So if your lines are already there when you drop, they will be included in the stored information and anything new that you add will build on top of them.