White slip 221(G) for H4 Extension

Hi,
Any of the valuable inputs on this will be very helpful. Thanks in advance!

My brother’s wife got 221(g) - White Slip while appearing for her visa interview appointment for H4 renewal at US Embassy (Mumbai) on December 10th 2021. They returned the passport and the 221(g) slip stating that “Submit the document of Permission to depart USA from USCIS” and submit the docs with passport when ready.

In order to get the requested document, she called USCIS and got to know that the final approval receipt is the only form of proof/documentation they can provide and nothing related to the letter stating that she was permitted to depart USA. Her USCIS account still shows the case as approved.

Some background regarding this 221(G) inquiry:

  • Application received 05/04/2020 - She was in US at that time
  • Biometrics completed in April, 2021 - In US
  • She had to travel to India on 05/01/2021 for a family emergency
  • USCIS Case approved on 06/10/2021
  • Did a dropbox in India and initially got 221(g) white slip July 2021 due to the ban.
  • Asked to get appeared for interview post the ban is lifted.
  • Appeared for interview on December 10th 2021 as requested and got the above 221(g) white slip requesting the USCIS document

Now, what else she can submit or what should be the next steps to clear this inquiry and come back to the USA.