I would chuck in some rabbit for them , more than they can eat , then get them out after they have gorged on the meat , keep the area they have to roam free fairly small & have a box in the run they can go to if they become scared , sides & roof equalls safety ,
do they have free acess to the run or do you have to take them from the hutch to the run ?
just found the thread when you posted pics of the hutch & run, i would make a bedding box & place it in the run if you havent already done that