Correction to my 27 Oct 18 - 06:35 PM
The impossible events attending Sven's return are there in the early version. And I agree that his having murdered his brother is suggested, but it's not explicit, and I'm used to ballads stating what happens in simple terms rather than by allusion.

BTW I take "i Roosengård" (with whatever spelling) to mean in a place with that name rather than "in the rosegarden", both because of the capital letter and because there is no "-en" definite article.