As it was they were both right about two things. The basilisk eggs were not suppose to be mixed in, but a shop that had been raided may have switched the eggs to keep one or two of the dragon eggs. Either that or they didn't know their eggs very well when the smuggler sold them. No matter what the reason the box that had been examined may have felt a bit lighter and a small hole might have been noticed if one was looking closely, but if one was looking closely enough they may have noticed something small slither out the door as they entered.

As for the box the man had peeked in and noticed some broken eggs, he may have noticed a small spark that set the corner of the box on fire. The small dragon had escaped from his egg and was trying to find his way out, he didn't mean to step on a brother or two's eggs while he was in search of the light or his mom.