I don't make folders, but here's my thoughts...
I think you could get away with it (depending on where you drill you holes) if you used a small threaded insert or standoff in there... that is, drill the holes in the wood the same diameter as the standoff and sand the standoffs flush with the backspacer, then the screws would have something to work with. The wood would be purely aesthetic as it wouldn't have any real mechanical purpose, but it could look nice depending on the design.