It not very clear what type of Schengen Visa you are applying for.
I assume your an Indian citizen travelling from the US to India.
For a flight transfer using an internal Schengen Area flight a normal C-Visa must be applied for
- New York --> Paris --> München --> India
For a transfer inside a Airport International Transit Areas, Schengen Countries will require a transit C-Visa from you since your US H-1B has expired.
Holders of a valid Canadian, Japanese or United States residence permit do not need a Transit Visa.
The form I797 is probably of no interest to France (or any other Schengen Country) unless it is a
- Form type I-797F, Transportation Letter: Issued overseas to allow applicants to travel.
Assume that forms of other countries are of less interest than visas when applying for a transit visa.
Since your VFS seems unable to assist you in this matter, you should apply for the needed visa type directly from the consulate of first entry.
If you are planning to return back from India to the US in the near future, that expected date should also be given.
In such cases a multiple entry visa may be issued.