Have you tried putting them in a separate pen w/o access to coop/nest boxes?Could they have been hiding eggs? The longest I have ever waited was three days to get eggs... but I had been consistently getting eggs every day or two when I found those.
The two that refuse to break won’t even walk out when pulled off. They just scream and sit where I set them. Then walk back like zombies! I have set them out of the run and I had to block them from running back in. One is a barred rock and the other is a Barnavelder. Both new breeds for me. And I thought Buff Orpingtons were nuts! Lol