See many other threads. The cello's name is on the PNR, the cello gets the EQMs/RDMs. I presume there's a special desk at NW WP, just for keeping ahead of any trouble, related to people traveling with cellos, guiters, etc, of especially high value. The good news is, I presume you're managing the cello's account, so figure that the cello can be very good to you, when it comes time to redeem those miles!

[edit] I presumed double-RDM was for "convienence seats". Then again, haven't you always wanted to introduce "my cello, the Plat"?!

Steve B.