Tax return transcripts are downloadable from IRS website for free.
Yes, petitioner can scan and send copy of affidavit of support by email. Signatures should be wet ink, not electronic signatures.
A valid ID is required to get to oath.
From what I remember, GC was enough to prove my identity. However, how it works with cards you're not supposed to have (e.g 10 vs 2 year) - I am not sure.
You no longer qualify for citizenship under 3 year rule. This is because you broke marital union requirement.
You need to withdraw N-400 and probably convert I-751 to divorce waiver if you're divorcing.
She must be living in marital union for 3+ years when applying for N-400 under 3 year rule.
Would she be living with you for 3+ years physically together when applying 90 days early?
I believe it. I also believe most of detained people either travelled to destinations deemed unsafe by DOS or have links / posted something on social media affiliating with questionable organizations and groups.