USPS Fraud?

So here's what happened:

Over Easter weekend I left my phone in Dallas. My Dad found it and mailed it to me on March 31, with a tracking number. The tracking number shows DELIVERED on April 3 at 3:58pm, signed for by J****, a worker at our apartment complex.

Only I never received my cell phone. I checked back many times, nothing in the office, nothing in my mailbox. I called the post office, who claims that they can do nothing about it because someone signed for it. I talked to J****, who says that the post office worker who delivers our mail has them sign for packages, then she takes them over to the main mailboxes and should leave us a key to retrieve them. No key. This is not the first time this has happened, though before, I made a lot of ruckus and they always eventually "found" the package stuffed somewhere.

I must interject here that the post woman who delivers our mail is THOROUGHLY INCOMPETENT. I have never had a package arrive on time. Once, the only time she's actually delivered something, she literally threw it at me and ran away. I lodged an official complaint with USPS; last I heard, it was "forwarded to [my] local office."

So, I gotta say, this woman has pretty much got it made in the shade. She's got gullible office workers signing for packages they've never seen. I filed another formal complaint with the post office investigative services (which, I just found out, has about as much power as the FBI) but I don't have any hopes of ever seeing my phone again. I'm really sad about this as I had irreplaceable contact information, photos, and videos on that phone. Technically, the apartment complex is legally liable, so I am going to get a replacement phone from them (if I shake enough cages) but I hope that, if this worker really is stealing mail, she's eventually put in jail where she deserves to be. I'm not the only person in this apartment complex missing a cell phone...