I'd go with how your son and his friend feel about it. If they don't object, file a police report. I'd go with sooner rather than later.
CA
Most days in life don't stand out, But life's about those days that will...
A while ago I dated a divorced guy, who suddenly got custody of his teenage son. Mom called during the night to "come get your son." What the lad didn't take with him THAT night was thrown out or destroyed by the mother, including killing his kitten. The woman was a drug-head spiteful piece of work. And my BF was a cop. So yes, a report was filed with the local police department (the agency he had worked for before transferring to Parks).
The Mom was on a power trip, angry at her son, but what she did was seal her fate and is no longer a part of her son's life.
*****
So unfortunately beccaB the disfuctional parents may still have it, or it may have gone to the dump with the rest of the younglady's belongings. Hopefully she's in a stable home, and can remain there. Unless she can return home to retrieve anything left behind, with an escort, it may be a lost cause.
I'd list it stolen with the local police department, but unfortunately you probably won't see it again.
Beth