Pages referring to other folklore collections that include Scandinavian tunes:

https://moeticae.typepad.com/mi_contra_fa/2012/06/roland-more-help-from-sweden.html
https://moeticae.typepad.com/mi_contra_fa/2012/03/roland-wait-i-take-it-back.html  <-- this is the main one
https://moeticae.typepad.com/mi_contra_fa/2012/03/more-on-roland.html

Website with amazing number of sources on it worth another look later: http://www.germanicmythology.com/PoeticEdda/Voluspa.html

Asatru chant for Voluspa, does not use the tune I've found, unclear where tune came from: https://www.youtube.com/watch?v=xisBERxHJ6g

1921 book, translations of some hattr, some sagas, and some rimur ballads.  https://www.gutenberg.org/files/33471/33471-h/33471-h.htm

Website dedicated to a 19th cen Icelandic poet, includes some information on poetic styles (of his time, I think): http://digicoll.library.wisc.edu/Jonas/Prosody/Prosody.html

Program from the 2018 Nordic Harp Meeting, with seminars/classes addressing a lot of the same things we're grappling with. Look up the instructors?  : https://nordic-harp-meeting.eu/wp-uploads/2018/10/Programme_book_NHM2018.pdf

Elementary school website, but contains some references to track down later e.g. Sean-Nos singing: https://www.downsjuniormusic.com/anglo-saxon--viking.html