It's this definition of raid: "quickly and illicitly take something from (a place)" (versus the law enforcement version, where illicit is used instead to describe the goods which are taken by the police).
If the PI brings a bunch of big goons with guns and they imply that they'll kill you if you don't turn the thing over, then sure, that's a raid. But also you'd presumably call 911 immediately and file a police report stating that you were robbed.