UA 4641 then WN 1844 at Denver
Durango → Denver → St Louis
Timetable, Denver time
06:34UA 4641 from Durango at the gate
19:20WN 1844 to St Louis leaves the gate
12 h 46 apart on the timetable
WN 1844 leaves 12 h 46 after UA 4641 arrives on the timetable: more than half a day, so not a connection we count.