Oh, ok. Well, looks like I'll just have to incubate one of the eggs and see what happens. I checked some reference photos of chicken eggs at different stages of development so I have a rough idea of what to look for.
The good thing is that these white eggs are extremely easy to candle. You should be able to use something as simple and as common as the flashlight on your smartphone and see very distinct veins and even a moving embryo which is very distinct from a blood line or infected egg.
Here is an example of one of my Trader Joe's eggs: