applying the TSG process to serious behavioral issues

In 2016 we adopted 5 siblings from fostercare (4 birth fathers, 1 birth mother; lots of abuse/trauma/etoh/drugs) and things have worsened greatly since COVID started, and with late-adolescence. There are some serious diagnoses such as ODD, BPD, perhaps somewhere on the RAD spectrum. My husband and I are planning/committing now to use TSG to 'push a re-set button' on family norms/behaviors. The children living with us currently are 12, 16, 18, and 21 – although developmentally younger than that. – the kids are all in therapy and some are on medications. the youngest two (boys) are sometimes violent, swearing, stealing, vandalising. How do we apply the Rule of 3 with some of these more seriouis issues. The kids seem to have great potential and we are hopeful for them – but also my husband are just trying to survive – as individuals and as a couple. (we would welcome prayer from a distance, from anyone!)