The owner of Rosen was involved with BAGS, Inc. I question if BAGS, Inc ever would have been able to develop RAC without Disney. I have no idea how much help Disney provided to BAGS but having the Disney contract "in the bag" had to have given BAGS, Inc a lot of credibility. I'll speculate that's why Disney is able to offer the service for free.
Note that Bags, INC did this for the cruise line industry before Disney ever signed up for it. So, this was not created for Disney, but they bought into it and have become one of the largest customers.
As to what happened, it's hard to say. However, there is no random selection of people who are inelligable. That sounds like something they are saying to explain away problems they are having. Everyone should be eligable as long as their data is in the system.
However, just because you called BAGS and they found your reservation, does not mean that the person at the hotel counter would be able to find you. It *should*, but... well, it's complicated.
One of the problems is that there are still seperate screens they are using at BAGS to accomidate the different airlines as not all of them are running under the same interface. There is a new version of the software that we are working on which will allow all the airlines to be in one screen, and will most likely solve some of the complications the agent was running into.
In any case, I am not aware of anything in the software that could have caused this hiccup, so more than likely it was as the OP said, and the agent tried to do a workaround that was not functionally correct in this situation.
Sorry for the hassle, OP!
In any case, i'll keep my eye out for any bugs that can cause similar issues.