Originally Posted by callum9999

I'd be incredibly sceptical about this, but given the company allows you to open and inspect the package I may consider it.

Being allowed to inspect it greatly reduces the risk, though once at the initial security checkpoint I'd ask them to thoroughly inspect the item making clear it isn't mine.

That being said, there's still a (very small) chance they won't detect anything (or don't look hard enough) but the security on the other side does. Pre-security with proof that the parcel isn't mine and that I've highlighted it's a possible "risk" to security is one thing, being in a foreign, possibly hostile, country with it is another!