Dalton Brothers survived Coffeeville?

I don't know how many times I've watched this movie. I just never caught this goof until the other day.

When Bud says he is going with John and that they'll be famous like the Daltons, John replies that the Daltons were dead having been hung.

Three of the Dalton brothers, Gratton "Grat" Dalton, Robert Rennick "Bob" Dalton, and Emmett "Em" Dalton all participated in the infamous attempted two bank robbery in Coffeeville, KS on Oct. 5, 1892. Grat and Bob, along with two gang members, were gunned down and killed by town's people. Emmett, although shot some 22 times, survived. He went to prison until 1907. He died in Hollywood, CA July 13, 1937. An older brother, Frank, a US Deputy Marshal, was killed in the line of duty on Nov. 27, 1887. The Dalton's criminal career lasted just over four years. The photo taken of the four killed in Coffeeville is one of the most famous photos showing the eventual end of those who flout the law.

I didn't double-check the dates. So, they might be off. Basic facts are still accurate.