If your worms are all heading south, (or north), there is something wrong in the working bin.
Most likely...too much food.

yeah sounds like there is something in the working bin they don't like. (too dry, too wet, too much food, ) I agree with Sqh1.. most likely it is too much food going into the bin. making the whole mess too wet and anaerobic.

Does the working bin smell funny?

are you getting any liquids in the leach tray? ( I try to avoid getting the bin wet enough to have any liquids fall down to that level.) If you have water collecting down there. mix dry shredded paper or dry ripped up cardboard to the bedding mix to try to dry it out a bit in the working tray.

Definitely something wrong up top. Maybe time to start over with fresh bedding and be very prudent in feeding.
Also, many folks over process food releasing way too much moisture - feed kitchen waste in chunks no smaller than 1" square or so. Of course there are exceptions, but generally, even though chunks take longer to break down and for the worms to process, overall this can have benefits.