Quick update just to close this topic - 2 months later we got both cases officially approved and waiting for Oath Ceremony! Calling to USCIS doesn't really help, Tier 2 just replied over email that case is inside normal processing timeline and local rep didn't want to take the case since it's been only ~60 days and recommended to give it some time. So we waited...
Thank you all! Whoever is waiting I wish to have patience, result will inevitably come!