Hi Rafael!
If that are eggs, perhaps they got thrown down from a leave or out of a cave when you where searching for the male.
Normally the Paros make them to form a clutch.
But if you didn’t find the male and those white eggs are fresh perhaps the female lost them without being fertilized?
But I can’t believe, as you described your emptying of the tank, that you failed to see the male …
So let’s go on to give the girls another man next weekend!