UA 3905 then DL 1389 at Houston
Cancún → Houston → Detroit
Timetable, Houston time
13:29UA 3905 from Cancún at the gate
05:10DL 1389 to Detroit leaves the gate
15 h 41 apart on the timetable, overnight
DL 1389 leaves 15 h 41 after UA 3905 arrives on the timetable: more than half a day, so not a connection we count.