Can anyone identify this music(Yes related)?

So, anyway, this video was taken at a Yes convention back in the late 80's(87 to be exact)in NJ. Maybe some of you were there. I actually was there for one day but didn't take the video. What I'm trying to figure out is what is the music that is playing from 1:39 to about 2:12. There are two ostensibly different musical segments in there. One goes from 1:39 to 2:02 and the other goes from 2:02 to 2:12. I recognize the stuff before it and the song after it. I won't spoil it in case anyone wants to name those as well just for fun. The intro music in general starts at :30 and goes to 3:05. I'm guessing but not 100 percent certain that it's all Yes or Yes related. If it is actually Yes then it must be rather rare or some outtake that I never heard. I don't have all of the later remastered cds(yet).

Anyway, here it is. https://www.youtube.com/watch?v=fxaQShW-n3c&t=180s

Unfortunately I wasn't able to embed the video in here but this one plays fine(not counting the actual video which admittedly isn't perfect. Lol).

That is a pretty kick-ass passage.   Sounds like White on drums, and surely the material was recorded between 1977 and 1982.   That's the best I got.

Makes you realize how much quality material they had at their fingertips.   The studio albums may've been just the tip of the iceberg.

I'm not as much of a Yes expert as some people but I'm pretty sure most Yes material has been released either on the remastered cds as bonus tracks or on the Yesyears or other Yes compilation albums. There are of course a lot of solo albums that feature Yes members as either their own album or as guests.