The Explosives and the weapons were provided by the uncle in law of the guy.
No idea were he could get this, maybe from eastern countries, shouldn't be that hard if you ask to the appropriate person, especially around Paris.
Plastic is not only used by terrorist, but also by thieves to blast secured lockers and so on.
Some contacts in Corsica would help
The Bagage handler was returned his pass and duty at CDG since.