While I have never left azureus eggs in the tank (I have done this with vents), I usually get most to form into tadpoles. If you put just enough water in the petri dish to cover the bottom, they shouldn't ever dry out because they should always have some contact with water. I wouldn't submerge the eggs though.
This is exactly what we do:
Upon finding eggs, leave them in the tank for at least 24 hours.
Remove entire petri dish and set in a tupperware bin with wet papertowel on the bottom.
Spray water in petri dish until bottom is covered.
Cover tupperware bin.
Let sit in room temp until hatched (heating them can often dry them out too.)