Only solution to protect workers and crafters is to make 0 mot dueling available at duel lvl 250+.
lvl 120-150 0 mots are same as lvl 30 or 40 0 mots, there is no difference. If level 120/150 went xp dueling it wouldnt take long before he would get out of range of those workers/crafters.
i didnt say the new duellers at level 120 where zero mot duellers
also those workers/crafters are constantly going to be duelled by different duellers coming into their duel range! they'll still get slaughtered just now it will be by different duellers every month