Bad eggs - safe to eat the chicken? *pics*

Hi guys, for the past few months, my Buff Orpington (2 yrs old) has been laying very ugly bad quality eggs. I wouldn't mind so much if "ugly" was the only thing wrong with them, but they are extremely thin shelled, though I regularly give oyster shell and when cooked, the whites are very thin and runny. I cooked up some hard-boiled eggs for deviled eggs for Easter and hers were completely mushy and clearish when they were hard-boiled. She is on organic feed and occasional scratch, occasional greens and kitchen scraps of fruits and veggies. I let them free range once in a while for a few hours before sunset.
I don't think her diet is the problem as she is the only one of 14 hens to have this issue. Her eggs were not always like this, but when she started laying again after winter, this is what I got. Also, all my hens were dewormed right at the end of the cold weather. I don't have a problem selling her or eating her, but am concerned about eating her if she has this issue if it's a disease (though again, none of my other hens have this problem). I looked at egg drop syndrome but don't think it really describes what her eggs are.

You might be dealing with Infectious Bronchitis Virus (IBV.) Wrinkled eggs, thin watery egg whites are a sign, especially in a 2 year old hen. There are other symptoms that you may have missed depending on the severity of the IBV strain. Here's a couple of links, scroll down to Infectious Bronchitis and read if you wish.
http://edis.ifas.ufl.edu/ps044
http://edis.ifas.ufl.edu/ps039

I checked for any discharge and she doesn't have any and no noticeable signs of weird breathing. If she previously had bronchitis, would her eggs be like this forever? Also is it safe to eat HER?

Had a girl who never laid eggs that great, and by the start of her second year, her eggs looked like that. None of the dozens of other layers of her bunch had an issue so we ate her...