have you tried Asian soft fur rats they are supposedly a ball pythons natural prey.

just a reminder imports aren't always the best kept or treated the best while transported yes it has gotten better they don't go burn fields to collect what crawls out like they use to. but they still aint treated all that well and have more then likely learned to fear humans already

another option all though costly try hamsters and gerbils I've coaxed more then one snake thats refused to eat to eat them then you just wean them off them by rubbing a dead mouse onto the gerbil or hamster

also hate to say this but some babies just aint meant to survive and maybe by some weird coincidence you got a few of the babies in 1 shipment.

another option since you said you been force feeding stop for a few weeks. I've had babies go months with out eating to finally take anything and everything offered to them. try small prey if you breed your own mice offer them a few pinkies most snakes Evan adults love new born prey they dont have to kill it. yes it might take a dozen babies a time or 2 but that will get it started back to eating and on the road to gaining weight. there is supplements on the market now a day to keep non feeders somewhat healthy till they decide to eat. there is even stuff now a days that supposedly makes them want to eat.

also a few questions are you offering live or f/t prey? them being wild caught imports they aint use to f/t prey. also are you sitting there watching them when you offer food? i know my green tree pythons wont eat if i watch them. but throw a mouse in walk out the room for even a minute and they got it sometimes i just got to turn around. do you offer them food with lights on or off not 100% sure but pretty sure but don't balls usually hide away in the day and come out at night to find food?

above all else stop force feeding that is stressing them out. yes i know i been there done that and have lost a few babies along the way.(I've bought my fair share of wild caught and to me dealing with a wild caught and a captive born are way different). wild caught knew freedom and had it ripped from them where as captive born has known nothing but being in a cage and had there food given to them so wild caught are stressed out from the second you got them) give them nothing but the requirements they need then. if they can see out of there cage cover there cages so they can't see you cause at this point in time they see you they think your going to either shove food down there throat and get stressed or they see you they think your going to rip them out of there environment like the people who caught them did.

i myself have better luck dealing with wild caught then captive borns I've always got them to breed easier gotten the babies to take food easier(mainly cause i had Asian soft furs from the get go cause the adults were sometimes picky eaters and refused all other foods so kept a few breeding at all times)

I'll send you a couple links to those supplements i talked about higher up. if they work i have no clue they weren't around back when i use to deal in wild caught balls but from what i read about them they seem to be made up of vitamins and minerals and such

and also have you had them checked by a vet yet it could be something medical of why they are refusing to eat but honestly in my opinion they are just way stressed out from being ripped from there environment by people then they got sold to somebody else then to you at least if not going threw 2 or 3 other people first so seeing people stress them then throw on top of that you forced them to eat when they were stressed stressing them out even further. yes I've lost my fair share of wild caught herps to stress related deaths so try this

cover there cages for the ones that you had to force feed and just leave them alone for a few weeks they will start eating on there own yes there is the risk you could loose them to starvation but if you keep forcing them to eat your going to keep them stressed out which will cause them to get sick cause stress lowers there immune system thus possibly loosing them later on down the road or causing loads of vet bills to get them back healthy to start the cycle all over again

maybe Evan deck there cages out kind of as densely as there home in the wild would be thus making them think they are in the wild thus getting rid of a Lil of there stress at least that and there cage covered so they can't see you any time you walk in the room will help them tons

sorry for the so long of response just giving you tons of things to try that has worked for me in the past with wild caught imports