Yes this is within the US and isn’t a problem.

She must wait 4 years and 9 months from date of issuance to apply for naturalization.

I agree with my colleagues to refile if tracking unknown.

Yes that is a good sign to receive the EAD approval.

Yes this is an option and a viable one despite the H1B history.

Yes this is permitted and not a problem.

It can take 3-4 weeks so you should be patient.

Yes you may apply after 5 years for citizenship. Consult with an attorney for guidance.

Yes an expedite request is possible although chances are generally less at interview stage. Consult with an attorney for guidance.

Yes you should bring amended return to interview.