What are the release dates for Seinfeld - 1989 The Finale 9-22?

There seems to be a misunderstanding. The phrase "Seinfeld - 1989 The Finale 9-22" doesn't refer to an actual episode or release date.

* Seinfeld aired from July 5, 1989, to May 14, 1998.

* The final episode aired on May 14, 1998.

It's possible you're remembering something else, or perhaps there's a typo in the phrase you provided. Can you please clarify what you're looking for?