There was only one incident 5-6 years ago, where my wife was forced to pay for an extra bag by a check-in agent at CDG, even though she was Plat. To avoid too much argument, she paid for it on the spot and called in to the PSL as soon as she was in the lounge, and a refund request was processed. They even filed a complaint, and apparently corrective training action was taken.

While it isn't convenient if we end up having to pay at check-in and then claim it back, it would be an option. Typically the PSL is quite good with such things.