Never heard that BC9500 could do it (and still don't believe it...).
But, you are right that BM6500 shouldn't be able to do that. Somebody must have upgraded it - needs the separate RDS module, and at least the 7000 software or the complete CPU module, and little hacks on the tuner board or that upgraded as well.
Or, it could be some other mix & match job, like BM6500 case parts on a 7000. The rear type sticker is on the cover so that won't help, but did these have another sticker somewhere inside?