I've heard plenty of stories about immigrants in this era / the late 19th century having their legal names in the US be at the mercy of whatever the immigrant officials chose to write down. How common was this actually? Would this happen even to immigrants fluent in English who could clarify their real name? Did the immigrants in question get their names corrected or were they just stuck with whatever they got?
There's always more that can be said, but some time ago /u/edhistory101 answered Is it possible to estimate when a family immigrated to America by the length/ethnicity of their surname?, which discusses this story.