We are searching for the same lines.
My husband is descended from Marlene's brother Ole Bjerkeset. He had two sons. Ole Bernhardt Bjerkeseth immigrated to Wisconsin where he continued to work as a fisherman, and died fairly young. Peder remained in Norway - if I searched him correct. He is listed as Peder Birkseth in the cemetery records. (My husbands grandfather) Ole Bernhardt Berkseth's first son names one of his daughters Marlene. Just thought that was interesting, perhaps they were still in contact?
I have been working on my tree for years. It has been difficult to wrap my head around the no family last name thing, in the Scandinavian lines. After reading your threads I was able to explain it to my husband. I have been back tracking trying to find the documentation for the information I found on familysearch.com for this line of his tree. But looking at the birth records is making my eyes cross. The census records have been a great help. At least my computer can translate that.
From familysearch I came across Ole Olsen Bjerkeset parents were Ole Knutson Gammelseter and Malena Olsdtr Indergaard. But its unsubstantiated, I have not come across the census records to back it up.
I had him do the dna - but there are very few people that have researched out their lines outside of the United States. My husbands tree is online - but most definitely a work in progress. I appreciate the help you received, here in these posts.