I believe any destructible can be made to be walkable by checking 'walkable' in the object editor. I don't think this works for all doodads, just destructibles. Unfortunately destructibles always snap to the grid of the map even if you remove their pathing, but hopefully it will work. You can always use invisible platforms too, you can even change the angle of them by setting the pitch or roll to a negative value in the object editor. You may need a visible 'invisible platform' model that can be replaced once you have it how you want it. Good luck