I can help the School Of Scottish Studies with regards to this one. The "unknown" group are most likely from Aberdeen. That's certainly Tom Spiers introducing the songs and singing. 99% certain I can hear Arthur Watson joining in on the chorus. The 2 of them had a group at the time which included Sandy Cheyne on 5-string banjo and John Vittie on concertina. They may have been the other players. I can't say for certain because although I was in Kinross at the festival at which that was recorded, and remember seeing them there, I wasn't at that concert. You did used to get impromptu bands thrown together on the spur of the moment, but that arrangement sounds to me to be a bit "tighter" than that. There were several line-ups to the group, but I believe that was a very rare recorded performance by "The Ghille Mhor", which was a precursor to "The Gaugers".
Next time I see Danny C., I'll ask him for more information about his version of "The Knight", and what he remembers about getting the song from Jeannie.