We didn't really have an interview, per se.
The officer asked us to submit what we think is necessary, and we sat in the office in silence for maybe 30 minutes while our documents were getting reviewed.
No questions asked. Maybe a question or two confirming about our mailing address, but literally that was it.
They didn't give me an immediate answer at the spot, since they had to go over my medical documents that I took before my K1 visa interview in my home country.
They approved me 2 days later, so my partner and I are so relieved that this process is finally over.