I have used the same method that you are using for the last 3 years except I use less water and only one toothpick sized hole in the lid. I do experience dimpled eggs and fogged up containers about 10 days before hatch time. Same thing happens. I open the lid and they inflate. I do agree with Gregg. It seems that all those extra holes probably dried your eggs out a little. 30 days is too early for dimples.