Using influence for job termination and mental harassment

Dear Concern, I writing this request regarding, get suggestion about my brother job. My brother was working in a financial organisation which is in New Delhi. After working 6 months in that organisation my brother feels unsatisfied and mental harassment in his work rude and dull behaviour of organisation owner and his son abusing and intolerated. So my brother decided to left the organisation that while during that, one day my brother forget an important mail to sent and after knowing that the organisation owner come to my brother and start abusing in front of staff and ask for my brother last salary slip and said that "I 'll pay you when you show me your last organisation salary slip and paying you too much you are not desirable for this" my brother replied " after six months you wants to know about my last organisation salary" my brother decline the whole debate and get his bag diary and left the office. After some days my brother gives the diary of that organisation and say sorry for that debate and left his office but that owner not respond. After some time my brother get the job in same filed a reputed registered company but his last organisation know that and start pressurising the organisation that terminate my brother otherwise I will not give you sales business to your organisation and accused my brother that person stolen importance documents of my official work and debates with me while working in my office and abuse me a lot which is not true. Recent organisation give 10 days to my brother to solve out your issue or not so find a job somewhere else my whole family depends on my brother my dad is retired person and I am preparing for civil services. Please kindly suggest something that my brother still work and ego of that influence person will get down. Please