Ever since engineering tinkers were made to stack with regular enchants the armory has not shown them. Since WH uses the armory as the source for it's data WH also does not show them.
The good news though is that you can put a regular enchant on your gloves in adition to your tinker.
EDIT: OOPS! I guess the Armory is finally showing tinkers. Sounds like WH need to be updated to reflect this. (no preasure