"Woody had no tolerance for racism."

True, but it took him a while to get to that position. Ed Cray writes of Guthrie, in 1937 or so,...

Woody Guthrie: A Place of Celebration and Pain

Short version:
It wasn't a misunderstanding or naivete. According to the document record, Woody Guthrie penned an original, full-blown minstrel coon shout newspaper satire just months before, or after. We can't say. The biographies don't even bother to get their dates in order.

However the same authors all do agree in having Woody refer to Mexicans as “pepper bellies” on AM radio-X in Tijuana two months after his alleged conversion. They kicked him off the air entirely for that and more.

Meanwhile, according to Woody Guthrie's own autobiography, none of the incidents ever happened and he never possessed any kind of racism to repent in the first place.

Somebody's been telling tall tales.