As others suggested, drill and tap. On my alu CAAD4, PO torn the piece out leaving a martian crater where the orig screw holes were, I drilled a small hole size of a needle just to guide and let a wood screw to make itself comfy.
Barbarian as hell, but it works, actually it just has to keep thing laterally stabile, since the cables are anyway holding it, but its strong engough anyway. No epoxy/etc.. was used.