Additionally, all miles ended up being credited without having to do any retroclaims, including for my previous DUS-LIN-GVA and vv trip. I made sure at each check-in that my number was clearly in the booking and on my boarding passes, but the miles and XPs showed up in an odd fashion. For the return itinerary they showed up 2-3 days later, then the miles and XPs for the outbound appeared a couple of days after that. So maybe the relevant miles and XPs get credited for Alitalia only once the entire itinerary has been completed.