If you harvest by making piles, make a pile on top of the new bedding so the (baby)worms will not only go down, but also straight into the new bedding.
That was what I was doing: the babies just dug into little damp masses of material and stayed there. Yesterday, I found some that had actually dried out and stuck to whatever they happened to be closest to as I continued to sort for cocoons.
I do intend to have a business, which is another reason I don't want to lose too many to the garden. I just can't afford to make the big outay for the quantity of worms I need. The past year has been a time to research, experiment, and learn on a small scale, but I did kill off a large portion of the worms, so it set me back... That was the chicken manure debacle...I think I must have killed two thirds of my adults.

. On the bright side, they had made plenty of cocoons that I collected out of that mess and the number of babies is astounding!
I did discover what I did wrong with the chicken manure, though, while doing other research (on using purslane as part of the chicken fodder). I had allowed the chicken poo to just sit dry, thinking time would serve to break down the bad stuff. This is not so... The manure becomes encased in a dried shell that repels moisture and traps in the chemicals that convert into ammonia when water is added. Old chicken manure was also shown to be depleted of nutrients for plants, so fresh is better, but fresh has the problem of being in the wrong form for plant nutrients. The ammonia has to be converted by bacteria, and if you have poor soil, it is going to be slow at best.
I am running an experiment now with adding water plus vinegar to the chicken manure: the vinegar is an acid that provides hydrogen to convert the ammonia created when water is added into ammonium. Ammonium as a plant food was shown to significantly reduce oxylates in both spinach and purslane. I found that when I mixed fresh manure with water, it smelled strongly of ammonia, but when I added vinegar, the ammonia smell went away and the odor was just like wet soil... I will be adding that to a portion of my garden to see what happens, and specifically to some purslane I gathered and put into pots. I will test the purslane to see if the chickens show a preference for the one grown with the ammonium rich mixture. I will also test a small batch of worms to see if they can tolerate the vinegar treated chicken manure, and if they like it enough to eat...
Update: Put two worms on the top of a small handful...the could not get away fast enough. Will try another batch with less vinegar when I have a bit more chicken poop. I am not hopeful of ever making the chicken poo into a useful worm food, though. With the plants, I applied to a couple of corns, one set of beans, one portion of purslane, and blueberries. All got watered in, thoroughly, and it is raining today.