Not sure if this will help much since I didn't fish the river but fished the lake instead. We stayed at Vance's Resort a little west of Blue Heron about two weeks ago. As for the walleye we had our best luck by an island that had "Passage" painted on it. We would simply drift worms along the bottom. The problem though was that most of what we caught was in the slot so we had to throw them back. Remember the lake is in FMZ 14 and the river is FMZ 10. Since we were looking for some fish for dinner. we concentrated more on pike down at Cutler. We did see a few boats down there fishing for walleye but I am not sure how they did. If you decide to venture out that far be careful of the rocks and the wind.
Wish I could be of more help.
Good luck with your trip.