Can A Family Witness Be Prosecuted In Sale Deed Fraudulent

I bought land from my father my brother is a witness to the sale deed. Now they sold their land with same boundaries as ours, can i file a criminal complaint that they are fraudulently sold our land. As per supreme court witness cannot know the content of sale deed he is only witness to attestation of both parties. How should I proceed now. Will this work as he already took possession of our land with force, case is already pending in court but can i file a criminal case against him?