There have been Panjabi songs in Hindi films from the 30s, even Hindi songs based on Panjabi tunes. This is the earliest example I know when the tune and words of a Panjabi song from a Panjabi film were lifted by a Hindi film composer and lyricists.
Listen to 1940_Yamla-Jutt_main-koyal-vanger.mp3
Listen to 1941_Circus-kee-sundaree_main-koyal-baaGh-kee.mp3
Now you know!
Bharat 33 Lata Roshan