You're making something out of nothing here really. Robben isn't going to go out on the left, why would he when Giggs is there. Bergomi will keep tabs on Robben, and because he's not going to be attacking, it allows the spare man Passarella to go forward without leaving the team light at the back.
Fair point, actually - as it would be pretty much pointless for Robben to wander across the pitch in this particular match. If he does, it will be solely to escape his marker - and it will still be pointless.
So, yeah, fair enough - I buy Bergomi as a man marker.
I don't think the position specific criticism of Donadoni and Conti is anything either, as both were comfortable on either wing/flank.
Not sure how well Rossi and Bergkamp would work, though. Rossi isn't actually a poacher, or an ultimate finisher, or whatever he's sometimes portrayed as. He played fairly deep more often than not.
Of course, you could instruct him to stick to the box and let Bergkamp be the ONLY second striker, but in my opinion that isn't an ideal game for him. Even for Italy '82, his most iconic role, he didn't really operate as a box player in the sense you'd associate with a player who is often regarded - again - as some sort of pure finisher. His movements relative to Graziani in '82 - to use that again - were more complicated than that.
Anyway, you can clearly play Rossi and Bergkamp up front - it ain't that. But if you're selling Rossi as the sheer finisher here (which I think you are), then that is somewhat debatable.