Firstly @ibstubro , “sources told Fox News” does not make it a fact no matter how many times it’s repeated. The Tulsa police dept has not confirmed that any such delivery occurred.
I’m not saying this to belittle your concern, only to remind that we put too much trust in media reports.
Try ordering ammo online. It can only be done by bank credit card (no pre-paid) by a person over 21 years of age and there’s a confirmation waiting period while the card holder’s credentials are processed. It can not be shipped to a different address than the billing address for the card. A repeat customer may be registered with the company for faster shipping.
IF the delivery tip is true, the most probable scenario is that the boys used their parents’ credit card. Any number of nefarious activities can be done with a parents’ purloined card and it isn’t difficult for a child to access it. Ever leave your wallet or purse unguarded in your own home? Of course you have. Ever think, “hmm, what if my child wants to kill me?” Probably not.