You're right - from the one angle (the third picture) - when enlarged - looks like 1) damaged scales 2) possible early lymphocystis (or something else) The other pictures IMHO - do not look like early lymphocystis per se. If you look at various pictures online of Lymphocystis (on the skin) - they are often quite distinct - and not 'subtle'. I guess I'm not sure that it's possible to determine whether 'early lymphocystis' on the skin can look like flukes, a bacterial infection, another viral infection, an early fungal infection, etc. etc.
So - IMHO - it might make sense to dose prazipro either way - since there is next to zero risk, and if it turns out to be lymphocystis (or something else) - you haven't really lost anything (except the cost of the prazipro) IMHO. But if it IS flukes - you have treated them. Hope this helps - keep us updated