Maybe Idaho River Sports can contact Lesser for you. & rally to get some old footage, for say... a fund raiser for IRU? or, Idaho Rivers United can rally for the cause.
I have a old VHS of a kayak & canoe trip on the Bio-Bio. ESPN documented Nolan Whitesell & his pals. A 'first descent' of OC1 paddlers on the Bio Bio. A very fun time in 1990-91. I lent it to a guy in Ft. C... ya there, Evan? He's producing a film on the Futalefu, et al rivers in danger of being dammed. Last I heard, the Rio Aysen project was delayed/post-poned/declined. That is good.
Paddle with Abandon.