This is 2006. I think the 'level' of the potion that they are talking about is the strength of the potion: i.e. Philter of the Wolf IV > Philter of the Wolf III.
If you look on lucy, these have an assigned level with them:
http://lucy.allakhazam.com/item.html?id=96475
http://lucy.allakhazam.com/item.html?id=96476
The old potions do not.
http://lucy.allakhazam.com/item.html?id=14534
Personally, I'm not sure that the game's original code even had a way of keeping data of the creator's level upon creation of an item ID. I could be wrong though.