Just like baby rats are hard to see b/c there aren't actually HARD bone, the eggs probably weren't seen. Not solid enough to cause a shadowing or whiteness in the radiographs (x-rays). And maybe not enough calcium yet in the eggshells to make them appear white in the pictures. ?

I don't think there'd be enough rays to hurt the eggs, but I'm not a vet. If you can candle and see veining, they're probably okay. You won't know until closer to hatching........but Good Luck!