I am sorry but why do we believe the small piece of information that they supposibly confirmed is true???
Most likely they do not want to report if it was recently purchased..so they said "belongs to the house of Grimaldi" which is a very vague response...
How many royal houses even with the most glitziest massive jewels owned parure anything remotely resembling this "old" parure...it's not old..look at any royal houses going back 50-100 years...no one wore jewels in this fashion and with multiple colored gems... This is a recent design mimicking old style...I call it a 'feather' style