"Was that around the time the B & B Frightener went in?"
Les Barnes went in 74/75 (engine failure couldn't stay up on one and a night ditching with fixed gear) the Valentinich business was a couple of years later. The were a lot of interesting stories at the time and I think the consensis was that he was in Bass Strait the question was "what about the a/c".
I never heard of any resolution of the landing/fuel theft/TO incident at Colac that evening.