Unfortunately I don't have any idea where the name came from.
I've been working to discover that information, along with the origination of the names for several other Bitterroot peaks, for well over a year with little luck. It seems mountain naming is not important to the local historians. I guess they're not climbers.
"So I was sitting in my cubicle today, and I realized, ever since I started working, every single day of my life has been worse than the day before it. So that means that every single day that you see me, that's on the worst day of my life."
--Peter Gibbons (Office Space)