4.1. How to check the PID of an egg.
The only thing I can suggest for this step is that you keep the save state with the uncollected egg (which you know is the right nature/etc), but then hatch the egg, migrate it to the 4th generation, and use pokesav to see its PID. If someone has a better idea I would be happy to hear it, especially if it does not involve migration.
RSEDecode will display the PID of a pokemon; I believe it works with eggs too, if not there's always fast hatch.