I would say that the eggs look fine in the pic and that you don't need to add any water if the humidity in there is reading in the mid 80s (the humidity within mom's coils will be higher). Vermiculite holds humidity well and it's a fine choice for humid hides and nest boxes, although it might be a little messier than other substrates. :) If the mom felt things were too dry in there, she could leave them to soak before returning or she could urinate in the next box.
Good luck! :)