The little boat can be somewhat unreliable, especially early in the morning. Plus, I wouldn't guarantee that it will hold 35 people (probably, but it would be pretty close). The boats are supposed to start running about an hour before the parks open, so about 7 am at the earliest. Then you'd need to allow plenty of time to cross the lake (can't remember what order the route is that time of day, but you may end up at WL on your way), and then trying to get that many people on the monorail all at once at the CR - whew! Disney recommends allowing 90 minutes to travel between resorts, and at that time of day I don't think you can do it.
Can you find the group sales office phone number (or maybe the FW front desk can help) and ask them if you can make special arrangements for your large party?