Hi,
I am not related but I do have a guess for you, but since you do not have a birthdate this is only a wild guess, but some of your info matches so I just wants to let you know:
My guess is that his danish name was:
Laurits Greenaa Køhler
Born 15 june 1863 in the danish village Rørvig in Holbæk amt.
His fathers name was Georg Emil Køhler(t).
His mother was Chrstiane Dorthea Pedersen.
His fathers occupation was "skipper", which means seamand/captain.
You find this Laurits Greenaa Køhler living with his uncle in Rørvig in census year 1880beiing a sailor.
The Køhler family was from the danish town Nyborg.
I hope you have more info to check if this is the right family.
Best Regards,
danishgenealogist@yahoo.com