The mic looks like the overhead drum mic.
It's 9/4 8mm footage and he has LA 71 film too. Footage looks like his photos: https://www.youtube.com/channel/UCzlagiZLp7bkxGCrPu8rXuQ/videos
Seems like you're complaining about sound quality more than performance. As mentioned, summer 70 is prime Zep. I'd also include Bath Festival 6-28-70 as one of their all time highlights.