I think the Edward John does just perch.. It would be difficult to do walleye with a party boat setup, because the main methods for walleye involve trolling or drifting with fairly long lines..
I would recommend doing a charter for walleyes or salmoniods..Often 6 person charters are not full and they will take singles or doubles to fill up a boat.. You may even find find charters that cater to smaller groups, or father/son combos..