Hey mate,
I recently went through the exact same situation - and got approved without an interview; so I thought I had to chime in.
I filed with a divorce waiver right out of the gate even though I hadn’t even filed for divorce at that pint. My ex was being difficult, and avoiding court service and I needed the extension letter.
I front loaded the application with extensive documented evidence and wrote a cover letter that referenced each piece I provided. I also provided a letter explaining my situation, and that I was looking to file for divorce asap.
Fortunately my divorce didn’t take too long, so I took initiative and sent the divorce decree preemptively in the mail. About a year later I got approved without interview.
From what I’ve read though, I think the better option would be to file married jointly in case an RFE comes in before the divorce is finalized, and then once the divorce is settled - switch to a waiver.
let me know if I can help with anything else