It seems to look more like these...
As for pathogens... Many people keep the snails in QT for a sort of long time before using them in a tank. Changing all tank water a few times. I have heard 3 months. and others more like a month. This is a specific issue I have no direct experience in, so I would default it to others with actual knowledge.
Though most pathogens which live in SW
environment do not cross over to freshwater. Again specifics would need to be verified.
My main concern is that these are not the same snails as FW
nerites pics online of course, Zebra, Tiger, Tire track, Horned, Olive (pic above) Black, Sun, Crown of thorn, Bumblebee, red or black racers.
If these Pipipi snails can transition to FW
, then you might need to change their salinity gradually. Good luck with your project.