UA 3905 then AA 3967 at Houston
Cancún → Houston → Dallas-Fort Worth
Timetable, Houston time
13:29UA 3905 from Cancún at the gate
08:57AA 3967 to Dallas-Fort Worth leaves the gate
19 h 28 apart on the timetable, overnight
AA 3967 leaves 19 h 28 after UA 3905 arrives on the timetable: more than half a day, so not a connection we count.