Covering somebody else's song isn't "stealing" it. Did Dylan claim he wrote it?

The Wikipedia article for the song states that Dylan claimed writer's credit when he recorded it. That is false, the album credits say Public Domain.

Arrangements cannot, as far as I know, be copyrighted, mainly because enforcement of such copyrights would be virtually impossible. How close would one have to come to someone else's arrangement to infringe?

"House" goes back to Clarence Ashley's 1933 recording, but its antecedents go back centuries.

Personally I prefer Leadbelly's uptempo version.

I've never heard VanRonk's version so I don't know how close it is to Dylan's, but it's a moot point. Anybody can record any published song. A classic recent example is the Romanian 'Numa Numa' song ("Dragostea Din Tei"), there are several virtually identical versions available.