There is no guarantee of that if one does retain the open file descriptor.

before rename:

fstat the fd, get st_dev and st_ino.

rename

stat the new name. Compare st_dev and st_ino.

If the value matches, you renamed the right file. If it does not match, you renamed a wrong file. Without holding the fd, it is impossible to know if it is the right file.

"you renamed a wrong file" shows that "there's no guarantee that you are renaming the file you just wrote to".

In this case you know that you renamed a wrong file. In the close before rename you do not know that you have renamed a wrong file.

Knowing that something bad happened after the fact is not the same as your idea that there's a guarantee that something bad will not happen.