They might be up there. Most years they don't move into the coulee until summer and they hold on deeper rockpiles but it's always worth a shot. I'd try running up Crab Creek as far as you can and looking for beaver huts. There will be some slabs up there if the water is at least 56*. The Coulee will be loaded with walleye for sure though. Run up past the Rd M bridge, the Coulee splits into a Y. Fish in the brush at the point made by the Y in the Coulee (on your left hand side as you are running up). The walleye like to hide in that brush like bass and can be in water as shallow as 3'. Or keep heading up the Coulee and troll or drag a jig right along the willows.
Down in the Seep lakes check out Upper Goose if you get a chance. Hit the far NE corner and look in 15-22' of water. Watch the graph....all of those fish you see just off bottom are walleye. Get right on top of them and jig a grub tipped with a worm. You should clean up back there. Good luck.