TLDR: call United to fix the issue

Something similar happened to me when I booked a flight on EVA airways with United miles. I booked 2 tickets from LAX-TPE-BNE. When I searched the booking reference on EVA only 1 ticket showed as confirmed for LAX-TPE-BNE. The other ticket was 'waitlisted'. Just like everyone else, it was mission impossible to get in touch with EVA so I called United. United got in touch with EVA and realized the 2nd ticket hadn't been fully processed. Now I have 2 separate booking codes - 1 for each passenger. Flight is on 7/25... hopefully everything goes smoothly.