I dont think Ghost shells being hit would comparable at all to the Travelers shell which has been called the Travelers "flesh" in dreams of Alpha lupi. Ghost shells are fashioned or created, not a part of them.
English
-
<The Traveler orb is also a shell to the being within.>
-
Yes but it's shell is actually connected to it's being and has its properties embued, even connected while seperated as we've seen in Chamber of Night in D1, and the EDZ shard in D2. Ghost shell is fabricated from nearby metals and glass until their Guardians fit them with an upgrade.