Discharge or interim

Wife left from me 1 year back and filed dv case. I filed counter for me, and discharge petition for my family(family stayed separately from us).Then she filed interim maintenance petition. Below are my questions?

1. Which one will go for trail first, Is it Discharge OR Interim petition?

It is upon discretion of the  court but usually court decides interim application first.

2. I know where she is working but don't have proof. How to get the income details of wife? Can I request court to summon the company/Income tax department?

Yes, you can request the court to summon her employer / company  but sometimes complainant is having some kind of adjustment with the employer and have already strategize how to hide the income details. So your first priority should be to get the job details yourself. For this you can make some contacts in her office or find some contacts in P.F department