H1B I797B Approval hard copy mail lost

Hello Sir,
I transfer my H1B approved petition from company A to Company B.
After 6 months waiting new petition from company B also got approved and company B shared I-797C soft copy.
I asked company B to share the original hard copy of I-797C so that I can book Visa Interview Slot.
After one month, Company B saying that attorney did not received the mail at the same time it was not return to USCIS. The mail was lost.

Here my questions:

  1. Is it mandatory to have original hard copy of I-797C at Visa interview time?
  2. If attorney file an I-824, how long it will take to get the duplicate approval copy?
  3. What is the best way to get I-797C duplicate copy with out filing I-824?
  4. Can attorney track the mail and get the lost package?
  5. Can we use I-797C duplicate copy for SSN and driving license?
  6. what are all the documents will be there in the package sent to attorney?

Copy is fine and you xan use it for driver’s license.