mixed sibling group issues

i have an non relative foster sibling group of 5 the eldest A is 10 and with his biological dad in another state, the second eldest N is 9 and in my home the 3rd M is 7 and in my home the 4th D is 1 and in a foster home and the youngest Baby A is 5 months old ( place after older siblings were placed in my home for almost 6 months 07/2022. she was placed at birth 01/2023)and in my care. my issue is out of the three in my care /are N,M, /and Baby A, N is having major behavior issues. violence verbally and physically, flight response, 911 called often, electronic obsession, (aggression and anger if not given). He does well 85% of the time but the other 15% its level % with the aggression out bursts. I put in a 30 day removal request but the caseworker said the judge may want to remove the other two children as well. The 7 year old M hides when N gets that way. she is often found in the baby's nursery with my 2 yr old AD watching tv in the crib. and often times N does not care who is around our who he hits with items. he flings things everywhere (not aiming at anything in particular). at one point I had just put Baby A down in her swing and was trying to deescalate him when he threw a plate at me because I asked hi to wait for seconds while i finished making plates. multiple times N was hanging out with my family and Had major behaviors to the point my family is afraid of his behaviors, he curses at them, runs away from everyone and growls like a rabid dog. I want N to get the help he needs and we have tried three different therapies, changed medications, he was baker acted and has had 4 different times police were called. all for the police to tell us there is nothing they can do (even after he tried to hit them with a stick and successfully struck my 14 year old on the head with the same stick). The Sw make me feel so guilty because I don't want M and Baby A to leave my home they have settled nicely and M has done well and even stopped having accidents, made friends, bonded with my family, and has gotten all A's in school. she has joined cheerleading, baseball and wants to join the dance team. while N wants to do nothing but play video games and watch tv. ( we do have 1 hour a night where he can do so pending behaviors) but during off times we are all walking on egg shells because we don't know what will set him off. a couple of time i caught him tripping my 2 yr old AD. what are the chances of M and Baby A staying in my home and N being placed without them?