Quick fix:
You should find a BrowsGone morph on the head; when used, it hides the upper eyebrow layer inside the skull. Or set the material's transparency values to maximum, so you can't see it when rendered.

Not-so-quick fix:
The upper eyebrow material is supposed to have a transparency map applied so that it'll look like real eyebrows instead of Play-Dough. You can find an eyebrow/eyelash transmap for Michael in Free Stuff; it's by Newt.