He wasn’t the eponymous Two Dogs Fucking, was he?
There is a heritage site in Alberta called “Head Smashed in Buffalo Jump.” I think it was an actual site where they stampeded buffalo (bisons, actually) over a cliff.
There is, indeed. It even has the most-excellent URL: headsmashedin.ca.
Per Erwin G. Gudde’s California Place Names, the location was merely “COALING” [Station]. An A was added not to distinguish it from COALING B, but merely to make it more “sonorous.” Perhaps a process like our modern-day creations of “Tar-jhay” or “Club M” for McDonald’s.