I think feeding will help. I have a super that has new foundatiuon and they aren't drawing it out. We are in a dearth here and I think that's why. Noticed robbing going on, am going to feed all hives, reduce entrances.
I also replaced old comb with new foundation in a weak hive and fed recently. When I went back and looked they were drawing out the new foundation. Also, if comb is drawn out in some frames but not all take the drawn frames and put them to the outside of super, frames with foundation to the center. maybe this will help too. Good luck!
Try to learn something new every day and give thanks for all your blessings.