Carl and Bjørn are both male names. So, there seems to be a mix up here! Bjørg is a female name, but I don`t know if that`s the right one in this case...

There are several men by the name Bjørn Brakstad in Norway today, but no Carl/Karl.

The Brakstad name could also be spelled Bragstad (older variation), especially in old days they may have used both...

I could not find Jacob`s emigration in the Norwegian databases or at Ellis island - there are a couple of Jacobs, but not in 1920 - maybe he went by his patronym (father`s name), do you know who his father was, or if he used a middle initial?