The second line of both songs contain the same melodic fragment...
"And say a young buffer lies low"
"No more on the docks I'll be seen"
Other than that, the composer should be given ample credit for a new and original work.
Almost every song created contains elements of a forebear including sophisticated theater songs.
It's OK to steal if you create a good new song out of it. Why not use a song as a trigger for another one?