I am not sure, I don't have screws to try with. Well, at least not ones long enough, the DVD drive came with a set too, but those assumed a flat piece of metal.
I've also thought of a more... shitty solution.
It can only slide in and out, so if I don't really tighten them, and fill the void with something, it should be fine.
So... maybe hot glue to fill the gaps.
Or, since I'd already need longer screws, I could probably drill holes through the metal that's right below, currently just covering the plastic. Though that would probably stick out too much.
Meh, if I could think of more good solutions, I'd still go with the laziest one.