I was told that same thing back in the day. But the same guys that told me that bought into a lot of old wives tales (slit the throat, they never look up, etc.)
Since I have never read anything about "fear scent" from any reputable publication or seen evidence of it in my hunting career, I consider it to be a tall tale.
The foot stomp has startled me before a couple times, any other deer watching the ordeal, at the time, would have been warned something in the area was a danger. I'd think that any running or jumping deer would leave the "danger scent" if stomping produced the odor. Deer stomp in scrapes to leave a visual marking, and to leave the inter-digital gland scent, an that isn't keeping the other deer from scent marking the scrapes. I too, believe the deer warning stomp, is more audio- visual, then scent related.