Your only hope, if travelling alone, is to sweet talk the CSM
This is just so wrong. I think it manifestly unfair to distract or compromise the CSM in any way, but especially if one is a non-revenue non-entity employed by another carrier. The CSM has enough to do managing his or her crew and ensuring the comfort and safety of the other 400 or so people who have actually paid real money for their travel. If you want a better seat, do what 99.9% of the population does: pay for it. It's not that difficult!
I make no apologies for being so blunt. It's unacceptable to tempt or expect another to do the wrong thing.