The size mention is basically the size of an hatching right out of the egg.....of course they could have hatch much smaller than the average also.
At this size they are unlikely established feeder and here is what I would do to make sure they eat and become consistent.
You need to treat this the same way a breeder would with getting hatchings started.
Separate them and have them set up in a 6 quarts tub with aspen bedding, a 6 inches flower pot saucer, a water dish and temps of 76/78 and 86/86 do not allow any night drop when it comes to temps.
No more handling, not more soaking.
Once setup in their new setting wait a week to offer food, offer a live hopper mouse in their enclosure.
Once they eat 3 consecutive meals on their own you can start handling them.
Keep them setup this way until they are about 150 grams.