Iunno if it's just the backing vocals. But like oblivious, Hikari no Senritsu, storia, Kyrie (maybe Lacrimosa) definitely seem to have a lot of backing from Kajiura's productions. And if they're not old tracks then they're near perfect replicas, which, while impressive, would still be Kajiura, lol.
Aaaanyhooooooooo, my point was, yes, credit where credit's due - there certainly seems to be more stuff here from Takebe and the instrumentalists than I was expecting from the bootleg. (Granted I'm not familiar with how those songs evolved in lives during Kalafina's original run - I doubt I watched any of their post-Red Moon concerts more than once, if at all.)
I hope everyone who this was for enjoys themselves.