Tracing stolen device

I bought an Apple Watch online. The previous owner put it back to factory settings and removed it from his iCloud (Find my can not be used anymore) and then he sent it by mail to me.

The next day, the Dutch Post services let me know very specifically when the parcel would be delivered. One day later, the notification changed and ever since, the parcel containing the Apple Watch is unfindable. By law, the post services is not liable for this loss, so it seems that I am left empty handed.

However, I do have all the numbers of the watch. Can Apple trace the watch as soon as it is turned on by the person who is in possession of my Apple Watch?

Thanks for the response in advance.