What relief can be obtained against a falsely propagated case ?

Mother, aged about 79 years, is a widow of a retired District Judge, who earns nearly Rs. 35,000/- per month as ‘Widow Pension’ through ‘Family/Widow Pension’ Pay Slip’. Son, aged about 60 years, is a Lawyer who has almost retired from profession due to personal reasons and earns Rs. 15,000/- per month and still have to maintain his family. With an intention to put her son in trouble due to some personal reasons, the mother filed a case under Sections 12, 18, 19, 20, 22, 23 of ‘The Protection of Women from Domestic Violence Act, 2005’, which has heinafter been referred to as ‘the said Act’, against her son. Ld. Court ordered for issuance of Summon. But mother manipulate the process and arranged somebody’s signature to show that the son has received the Summon. Son was totally in dark about the process of such case. When the Ld. Court, on the date fixed, saw that in spite of receiving Summon, the son did not turn up, took up the matter for hearing and passed an ex-parte Order for payment of maintenance @ Rs. 10,000/- per month relying on the information supplied by the mother that she had no such income to maintain herself and the son earns Rs.1,00,000/- per month. In this way, the son could not raise the point that mother earns nearly Rs. 35,000/- per month as ‘Widow Pension’ through ‘Family/Widow Pension’ Pay Slip’ and he has a meager income of Rs. 15,000/- per month. Mother has thus fraudulently obtained such order of maintenance by misguiding the Ld. Court. The son received Summon of the Execution Proceedings and immediately appeared in the case and objected to such Order behind his back. But the Ld. Court pined that at that stage he had has nothing to do. Accordingly an Appeal has been preferred before the Ld. District Judge, for setting aside the ex-parte Order. Now, two very vital question arise the answer whichof is very much essential to me. 1) At this stage of Execution proceedings, can a petition be filed before the Trial Court, under Section 25(2) of the said Act for alteration of Order ? 2) If the Revision succeeds and the Ld. Appeal Court passes Order for setting aside the Order of the Trial Court, then what will happen to the amount which has already been paid to the mother ? Will the Trial Court pass Order for returning the amount ? Kindly help.