Possible lead?
From The Lost Media Wiki
https://youtu.be/SFbpN1spx2w?t=495
Skip to 8:15 if it doesn't do it for you. This is a 30 second ad, not 15. However it is at a train track, it's a PSA, it's from the 90s-00s and the figures are white and human-ish. It isn't AC, but it is JR (Japan's national rail company) and finally, it has the train track sounds every 2 seconds.
So far, it is the most similar advertisement I have seen. I'd be interested to hear anybody else's thoughts.