I have a theory on this. Wikipedia’s list of municipalities in Montana shows three “lodge” place names: Deer Lodge, Lodge Grass, and Red Lodge. The pages for Deer Lodge and Red Lodge don’t explain their names, but the one for Lodge Grass does. It’s a mistranslation of the Crow name for the place, but it does refer to the actual grass in the area. So now the author has two with no answer found and one with a natural explanation