Actually- I cross-trained as Bell Services when I did my program back in 2006. I worked at Disney's Old Key West and Saratoga Springs. Basically, I took guests' information and their luggage and passed it off to the bellmen. There were always plenty of bellmen around to lift the super heavy bags. Then, when people came back to pick up their luggage, I verified their tickets and got their luggage.
I was never trained as Dispatch, but those cast members were in charge of working the phones and the walkie-talkies. I don't know too much about their roles beyond that.
I enjoyed that role because it was a welcome break from working in a full-service restaurant, and I loved the other cast members I worked with. Sorry this isn't terribly helpful!