Hi,
I encountered a similar problem and I think I figured it out.
This happened for me when the Object I am slicing has no thickness, sometimes it shows the overlapping backfaces of the subtraction object with the slicer material, but only the inner faces. In some cases it glitches out and shows there artifacts like the OP encountered.
So what I did to fix it was, select the object and give it a thickness, in my case I could use a cloth surface with a 0.1 thickness.
I cant provide a scene file, since the objects are confidential.