Unfortunately the song actually being played in that Soul Train episode, which was the last episode of the 1991 season, was a song by B Angie B, and not the song playing in that youtube video.
Inputting the lyrics into something like shazam or soundhound gives me different artists sampling it, but not the original. It's like soul/funk/disco, though I'm not an expert of genres.
Three different artists have sampled the song. They are:
"Tony Tone - untitled ass intro". https://youtu.be/URGO9dgqmig?si=vDJWpgDoL-uub1JA
"Eli and Six the Northstar - Down & Out". https://youtu.be/nMgpnjEDCVg?si=Zmiqvsoze-MtoGLm
"Andy Ashley - Hope You Understand". https://www.amazon.com/Life-Unstable-Explicit-Andy-Ashley/dp/B083H4CX2S
Here are my butchered approximation of the lyrics:
(part of the chorus?)
Does anyone know this song?