Thanks Michelle & Bill. Bill, I am dealing with Zonitoides arboreus.

Well, I carefully took everything apart, scrubbed the vivarium background with a cleaning brush and scalding water, baked the hydroton & ABG separately (200F), bleached (5%) the plants, substrate divider, and vivarium lid, and now have a fan and heat light on the vivarium & background. I will let the fan and heat do their work until the background is completely dry for a few days. I'll let you know how it goes. I searched and searched the internet to no avail to find out if any of these methods will work!

My main question remains: will snail eggs survive desiccation?

I guess I'll know soon enough! Wish me luck!