You can't get their room numbers, but your EM can give you printout of the resorts(on Disney property) with the guests names and the days booked. As long as the booked through the special reservation number and stated it was for your wedding, they will show up on that list.
We had 140 people down for ours and I used the list to drop welcome bags off at the hotels...all 11 of them! We went to the front desk with the list and our bags, which we labeled with their first and last names, and they had them placed in their rooms for their check in. We had to bring the night before they checked in, the resorts would not take them any sooner, so that meant because of everyone checking in on different days we had to make a few trips. It worked out great, everyone got their bags and said it was nice to walk into the room and find a gift from us.