From your and other articles , it seems there are a number of endemic large mammals living in the lake that might give rise to 'monster' myths.... My problem is that an experience my wife and I had back in 2008 during a tour of Bolivia and Peru, can't be accounted for by known lake creatures such as manatee etc etc....
My wife and I were staying in the lodge at the top of sun island...We reported what we saw but no ;local naturalists ever contacted us... What we saw has remained a mystery... From the top of the island we spotted a 'wake' in the water in the port, which was not any sort of vessel.. Because of the distance, we realised whatever was causing the wake was much bigger than a local fishing or transfer boat.. We watched it for some time, and were convinced it was some sort of creature. but what..?? The mystery has always remained such... We have spent much of the last 12 years travelling and watched wildlife all over the world, but this experience is one we have no explanation for.... So any info on other large lake creatures that this might have been would be very interesting... Thank you.