I agree that the 1855 usage is not the later idiom. I like better the prototype from 1850 you gave in the other thread. It uses just a reference to someone’s “nine yards,” meaning an exceptionally long letter to the newspaper in a feud they were having in it, rather than “the whole nine yards,” but certainly is used idiomatically much the same as the later finds rather than a reference to physical cloth. Someone should get that into the Wikipedia article.