"Do you both have the same friend with a 100k cello?"
Nope. Nothing unusual about a $100K cello. There are quite a few of them. Most of the principal cellists in the major symphonies own one worth at least that much.
Right - I wondered about that. Playing the cello could be an expensive undertaking!
I just came back from Europe with an expensive instrument in tow. There was no problem carrying in on board. The security people just checked it thoroughly (as they should), and I was allowed to bring it on the plane. It's not reasonable to check in instruments. They are too delicate.