This is something like the Roswell of Bigfoot Lore. The story has been revisited again and again by journalists and investigators. Many of the details were held back or unverified until 1967 when Fred Beck, the principal witness among the miners, told the full story to his son. A book was written at that time and I recall reading about the case in a magazine probably three or four years later. Cryptomundo has a long excerpt followed by some good feedback in the comments section.

There is something very obvious that stands out about Fred Beck. I'd be interested to read what you all think of him and how he affects perceptions of this multiple witness case:

"There’s an account on the 1924 attack on 5 miners that gave the canyon its name. Miner Fred Beck gave his account to his son in 1967, and discusses the spiritual aspects of the Apemen, who he does not believe are entirely physical.

I Fought The Apemen Of Mount St. Helens, WA

Told by Fred Beck of Kelso, Washington; written September 27, 1967 by his son
© Ronald A. Beck, 1967
What are Abominable Snowmen? Fred Beck is qualified to tell what they are. He was one of a party of five miners attacked by them in 1924, the most famous of such incidents in North America. The incident has become a legend in the Northwest. He tells the real facts after 43 years of silence.
It is my intention in this book not only to tell you about the historic encounter I had with these mysterious creatures, but also to reveal to the public what I believe they are. Truth often is stranger than fiction, but the strangeness comes from the clouds surrounding our minds, not from the mystery itself.
This is not a large book, but may the largeness be conveyed by the picture I hope to paint of truth. Much has been written about that day in 1924, and I feel it right that I express my views at last.
To avoid embarrassment to the relatives of the other four men involved in the 1924 incident, I have not directly mentioned their names. The name, Hank, is a pseudonym of one of the main characters in the incident."

Much more to read here: