Dave,
Nothing to be sorry about; we're both seeking the same thing; an accurate attribution of the OP's coin.
I see your point; and have no idea why
Home - Edelweiss Coins - Your online coin and paper money store would call it a 1994 when your source is calling it a 1989.
Perhaps the coin was issued in the 6th year of the emperor's reign, which may coincide with the 1994 date (six years after 1989).
Don......
Are they calling the original posters coin a Heisei 6 ( 1994)?
Your link above shows a Heisei 6 coin.
If the original posters coin were a Heisei 6 coin, it would be the exact coin that is seen in your Edelweiss link (attached below).

It also would have been issued in the 6th year of the current Emperor`s reign.
It would also have the Kanji for 6 (
六) just left of the kanji for year (
年).
The original poster's coin has none of these features.
The Kanji on the original posters coin is GAN
元, which translates as
ORIGIN in English. This Kanji is used on all 1st year reigns, ie. showa 1, Heisei 1, Meishi 1, Taisho 1, etc, etc.
Here are a couple of links regarding the disputed kanji (6) and (origin):
Origin (元) http://www.manythings.org/kanji/d/5143.htm
6 (六) http://www.manythings.org/kanji/d/516d.htm
The OP`s coin is Heisei 1 / 1989 (The 1st year of the current Emperor' reign).
My source is the 2014 Catalog of Japanese Coins and Banknotes issued annually by the Japanese mint
独立行政法人 造幣局Dokuritsu Gyōsei Hōjin Zōheikyoku located in Osaka Japan.