Punishment for voluntarily causing hurt (Section 323) is imprisonment for a maximum period of one year and/or a fine of not more than thousand rupees, i.e. the accused can either be (i) imprisoned only - for maximum one year or (ii) fined only - for maximum one thousand rupees or (iii) imprisoned for maximum one year and fined for maximum one thousand rupees, both.
Moreover this is a non-cognizable offence, which means that the police does not have the power to arrest without a warrant, i.e. just by filing of a complaint, the persons against whom the complaint has been filed cannot be arrested, unless a warrant is issued by the magistrate.
Section 114 says that a person who has abetted the commission of an offence and was present while the offence was being committed, such abettor shall be deemed to have committed the offence, thus he will be liable to the same punishment as that of the main offence . In this case the punishment will be the same as mentioned in S. 323.
The police cannot investigate a complaint of the commission of a non-cognizable offence without the orders of the magistrate (S. 155 of Cr.P.C.). Whether the allegations are false or not, will be decided by the magistrate. Thus the wife and your friend will not be punished unless the magistrate finds them guilty, through procedure established by law.