Is it possible that the Koi you referred to in your video had 'Koi sleeping sickness' as opposed to KHV? Prescribed treatment from Japan for sleeping sickness is 85 F, no food and 1.006 salt. ....

Wow what great pictures of those worms! And the fact that the fish was doitsu (essentially scale-less) allowed you to pull the worms with the heads intact! I value the pictures highly. So, with those ....