It barely can reach 9k.
I haven't heard this release, but a sharp cutoff below 10kHz suggests some kind of encoding or audio processing error rather than any kind of artistic or production intent. The only similar instance I can think of is the George Benson Breezin' DVD-A which cuts off sharply at 16kHz where the later SACD reissue is fine, and full-range well above 22kHz.
I say this because to do this on purpose you'd have to go out of your way to lop off the frequency response above 10kHz so severely, by putting an extreemely sharp low-pass filter on the output bus. There's no microphones (aside from maybe a harmonica mic), mixing desk, or recording format with such limited bandwidth - even low-bitrate mp3 is faithful to the original frequency response up to 16kHz. You'd have to record at a non-existent sampling rate of 20 (or maybe 22.05, half of the usual CD 44.1) kHz to get this kind of aural haircut above 10kHz.
I can only assume there was some kind of weird bottleneck or error in the export or resampling (or encoding) of the original source material, which is fine, computers often don't behave as expected, these things happen all the time. What's not OK is that no one took the time to QC this properly (if at all) and it becomes a loss for everyone - the people who've bought it have lost time and money, the retailers are losing money on returns and exchanges, and the artist himself surely won't be incentivized to put further Blu-Rays out. Hopefully someone who actually knows what they're doing can assist him if he does want to carry on releasing music in surround.
