Yeah, the Buffs were there, but I personally knew F-4 pilots at Mountain Home, who said they also provided close air support to Khe Sanh.
Buffs were fast movers, compared to helicopters. The F-4s were just faster movers. Where I was, we had Vietnamese F-5s and USAF Dragon Flys. I got to fly with them a couple of times. It was quite exciting, especially when they lit the afterburners.
“...I personally knew F-4 pilots at Mountain Home, who said they also provided close air support to Khe Sanh....”
I did too. At least, they said they did and I never corroborated their stories.
Each B-52 could drop 50,000-60,000 pounds of munitions on one sortie. Each F-4 could drop 6,000-8,000 pounds. B-52s had better CEAs. Do your own math to decide which platform was more effective.