I would guide your friend to the Ball Python care sheet here which has a section "Why won't my snake eat?" that he should review.

I would strongly recommend that he offers live before he tries to force feed.

Find out if he's housing them together (if so, he needs to separate them). Have him go through that check-list and make necessary adjustments.

I got my scale at Walmart in the kitchen section. Reptile Basics also sells scales.