First off... 95% of all package's that are mis-delivered are the fault of the consumer. Typing in the wrong address for example. "1234 Main Street" is not the same as "1243 Main" - Trust me. As an investigator for UPS, I'd seen it all.
DHL can't drop everything they are doing to get your package back. They need to contact the driver. She/He needs to think about where that packaged was delivered to. She/He needs to go back there and get it, or try to.
You are covered in at least two ways here. First off, your credit card company. Secondly, DHL.
I understand you are upset, but you are freaking out over a very small set back. You're thinking someone is outside right now flying your P3 that they accidentally obtained. Have you ever had your neighbors mail delivered to you? Do you open it, or do you give it back to the mailman? Think that most people on this earth are good people. Most people will find an error, and try to correct it. Think eBay. It was built on the premise that people are honest. You can send someone, a total stranger, money. They'll send you what you paid for.
Very few people are believers in "finders keepers..."
Jimmy