I can confirm that it does modify the value of the file on disk as part
of the export process.  Additionally, the src_emacs_lisp in the header
does not export any results because by the time (buffer-file-name) is
called the code is living in a temporary export buffer which is not
visiting a file, note that a heading like the following would probably
give the result you're after

* name src_emacs-lisp{org-current-export-file}

similarly you want the tangling to be done in the original Org-mode file
(not the temporary export file), so that should be placed in a header
argument as well.  Try the following less evil version on for size and
let me know if it doesn't solve your problems.