If both "versions" of "ryoko" consistently yield different results, despite appearing identically, your assumption that they are the same value is invalid. The likely possibility is that there are unprintable characters in the string. If the file was generated under MS-DOS, for instance, you might be seeing a trailing ^Z or something. Newline conventions might also be screwing you up, but if you saw a quotation mark followed by ryoko followed by another quotation mark, that's probably not it.
I would try splitting the string up and examining each byte, printing its value. That way you can be sure the strings are truly identical. (That, or use 'eq' I guess.)