I would try to take a peek inside.

Several ways to do that. x-ray pops to mind first. I once knew a veterinarian that had a wonderful curiosity. We would bring him all sorts of stuff and he would x-ray it for us. Great learning experience. Perhaps you can find such a person.

Otherwise, there are a number of industrial fiber optic inspection tools. Might try asking a high tech machine shop or similar if they would take a look for you.

I have had some success in using the camera on my droid for such applications. The bone is probably translucent. Take it outside on a bright day. Put the camera to the opening and shield the camera/horn junction from light. The exposure meter should compensate the exposure.

I think trying to remove the nails would take a conservators skill.

Nomad