I got some eggs in the mail. The were wrapped well. One was broken. I just took 4 after candling that had no growth, and opened them and the yolks were broken. The other 3 are not hopeful iffy. I had put a silkie egg in there, and after 6 days of broody setting, it sat out overnight not sat on. That has some hope.
The USPS must have done a real number on those eggs to actually break one egg and break yolks as well.