You should be able to bend the feed lips a little. (But that can be a risky adventure, as some feed lips can be very brittle.) But, if you still have the mags and they don't work, you're not really risking much.
Bend them enough so that you can slide the tip of the 9mm round between them, right about where the case starts.
(And as you know, but others might not, standard 75B mags won't work. Or at least they didn't in my CZ-100.)