Are eclogitic diamonds formed where they are found?

eclogitic diamond stability zonesEvidence from an eclogitic diamond suggests that one diamond was formed over billions of years in those diamond zones.

The Botswana diamonds inclusions include organic carbon material (eclogitic) with inclusions near the centre dated as over 2 billions years old and below its surface a garnet crystal from over 250 million years ago.

How does this work with the pressure and heat needed to create diamonds, now over billions of years, in its own individual diamond stability zone combined with the subduction of continental plates?

This diamond adds to the puzzling mysteries of how diamonds are formed according to geology theory. For example the Russian Udachnaya diamond suggested by a geologist as looking like it was formed instantly?

Scientists discovered a diamond from a Botswana mine with “inclusions” separated by 2 billion years. At the center of the diamond lies silicate, incorporated 2.3 billion years ago. In the diamond’s outer rim, its lattice is interrupted by the presence of a 250-million-year-old garnet crystal. The diamond boasts the largest inclusion range yet discovered.
Ancient diamond ‘inclusions’ reveal shift in carbon cycle of early Earth | United Press International

The studied Botswanan diamonds are interpreted to have formed in different tectono-magmatic environments that involve mixing of carbon from three sources that represent: i) subducted biogenic sediments; ii) subducted carbonate-rich sediments and iii) depleted upper mantle.
Dated eclogitic diamond growth zones reveal variable recycling of crustal carbon through time

Diamond formation in cratons puzzle

The rate at which temperature changes with increasing depth into the Earth varies greatly in different parts of the Earth. In particular, under oceanic plates the temperature rises more quickly with depth, beyond the range required for diamond formation at the depth required. The correct combination of temperature and pressure is only found in the thick, ancient, and stable parts of continental plates where regions of lithosphere known as cratons exist. Long residence in the cratonic lithosphere allows diamond crystals to grow larger.
Formation in cratons – Diamond | Wikipedia

Nieghbouring diamonds but different cratons?

Davies and his colleagues analyzed 16 diamonds collected from Botswana’s Orapa and Letlhakane mines. Though separated by just 25 miles, the two mines yielded diamonds with remarkably different inclusions. Orapa diamonds boasted younger inclusions across a narrower range, dating between 400 million and more than 1.4 billion years old. Letlhakane diamonds featured inclusions between 700 million and 2.5 billion years old.
Ancient diamond ‘inclusions’ reveal shift in carbon cycle of early Earth | United Press International

Diamonds formed where they are found?

Could organic material be the source for the inclusions because the diamonds are formed at the Earths surface from local organic material?

Could the kimberlite pipes and lamproite diamond bearing pipes not be the evidence and process of how diamonds are moved from deep within the grounds diamond stability zones but the result of the event that transmuted material where it was found?