Do as I tell.
1. First get address of that employer where your wife is working.
2. Get recent 4 X 6 photograph of wife.
3. File application via RTI [ask in post office] anybody will guide you to fill up the RTI form, asking details of wife's employment tenure etc.
4. Move your arse, approach the wife's employer and give an application in writing asking details of her employer. If the employer denies to give any information follow next step.
5. Also file an application in magistrate court where she has filed DV asking call of records, provide address of the employer as well as the photograph.
Once it is proved that wife was at the least previously working and is now not working due to just claim alimony from you, her plea of claiming maintenance will be dismissed.
All the best.
6. Ask in separate application to summon wife's employer.