Not sure it is bugged at all. Not that long ago they moved a bunch of skills around system wise, so that they no longer triggered global cool downs.

As far as I know the only 2 skills that trigger the defector doff are Gravity Well and Tykens Rift, they are also the only 2 skills that are on the deflector global anymore... so I would say the doff is working as intended... however it is possible the tool tip is wrong.