Formula: Enchant Weapon - Icy Chill scripted ?

Hello,

I would know if the Formula: Enchant Weapon - Icy Chill drop is correctly scripted on the Anguished Highborne at the Wintersprings. item=16223

I'm about 600+ kill and still not drop.

I'm on Outland server Burning Crusade

Item was delete from the table loot after the 4.2 version but still obtainable previous versions
http://www.wowhead.com/item=16223/fo...ll#comments:40

Thx

Kill count +150 no drop 15/06/18 at 4:30 am UTC+1
Kill count +150 no drop 15/06/18 at 5:49 am UTC+1
Kill count +135 no drop 15/06/18 at 6:50 am UTC+1

Drop chance estimated with the almost 600 farmed 2 days ago < 0.096%

Data base of same version is near 1% for this enchant