See first of fall criminal conspiracy is an offence when there are other offences without offence there is no criminal conspiracy. So your lawyer is correct there has to be some offence conspiracy can be clubbed with.
And till acquittal wait for defamation case.
If any person submits false evidence before court than it is offence of perjury and punishable under section 193 and 195 Indian Penal Code and shall be raised at time of trial but if the truth has come to knowledge after trial a perjury can be filled and you have strict evidence to same.
Section 193 in The Indian Penal Code
193. Punishment for false evidence.—Whoever intentionally gives false evidence in any stage of a judicial proceeding, or fabricates false evidence for the purpose of being used in any stage of a judicial proceeding, shall be punished with imprisonment of either description for a term which may extend to seven years, and shall also be liable to fine, and whoever intentionally gives or fabricates false evidence in any other case, shall be punished with imprisonment of either description for a term which may extend to three years, and shall also be liable to fine. Explanation 1.—A trial before a Court-martial; 1[***] is a judicial proceeding. Explanation 2.—An investigation directed by law preliminary to a proceeding before a Court of Justice, is a stage of a judicial proceeding, though that investigation may not take place before a Court of Justice. Illustration A, in an enquiry before a Magistrate for the purpose of ascertaining whether Z ought to be committed for trial, makes on oath a statement which he knows to be false. As this enquiry is a stage of a judicial proceeding, A has given false evidence. Explanation 3.—An investigation directed by a Court of Justice according to law, and conducted under the authority of a Court of Justice, is a stage of a judicial proceeding, though that investigation may not take place before a Court of Justice. Illustration A, in any enquiry before an officer deputed by a Court of Justice to ascertain on the spot the boundaries of land, makes on oath a statement which he knows to be false. As this enquiry is a stage of a judicial proceeding. A has given false evidence.
195. Giving or fabricating false evidence with intent to procure conviction of offence punishable with imprisonment for life or imprisonment.—Whoever gives or fabricates false evidence intending thereby to cause, or knowing it to be likely that he will thereby cause, any person to be convicted of an offence which 1[by the law for the time being in force in 2[India]] is not capital, but punishable with 3[imprisonment for life], or imprisonment for a term of seven years or upwards, shall be punished as a person convicted of that offence would be liable to be punished. Illustration A gives false evidence before a Court of Justice, intending thereby to cause Z to be convicted of a dacoity. The punishment of dacoity is 3[imprisonment for life], or rigorous imprisonment for a term which may extend to ten years, with or without fine. A, therefore, is liable to 3[imprisonment for life] or imprisonment, with or without fine.