[Azaghal]

Thanks for your advice.
There may indeed have been mod changes since I last played. It's almost three years and I don't remember Faldorn being so strong. But of course I installed Tactics to beat her with my own two (twelve) hands, not by ignoring or outCLUAing her. So I learned the hard way - about my own stupidity. It is actually possible to hand equipment from outside the pit to the champion inside. You don't have to throw it (as I assumed), you just have to place an NPC close to the pit (for me it was a spot directly next to the stairs) and hand stuff from inventory to inventory. Maybe it is not the way it was planned, but it's possible.
Against a prebuffed kensai with magical weapons and healing potions Faldorn didn't last long. Hail the Hero of Trademeet!