Few things I noticed from the pics.
1. Odometer reads 009999 as the total miles on the bike. Not sure what kind of tire comes stock on the FZ6, but I doubt it came with the PR3's or that he had them installed to replace the OEM tires the day he took delivery of the bike. As such, the tires likely have a good bit less than 10k on them.
2. The tread on the rear definitely doesn't look like it has 10k on it.
3. Look closely at the center sipe of the tread - between the chunks it's almost worn through and gone, but if you look higher on the tire (just below the shadow) it appears to have plenty of depth left. Leads me to believe that section of the tire that chunked wasn't cured properly which is the likely cause of the failure.