I think it is very possible that Vincent will dig them up. But my money is on them dying in their graves buried alive.

Or even better, Vincent does dig them up, but only nikki is alive and she takes the diamonds, runs off into the woods. Then the losties think someone dug them up to get the diamonds.

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Doctor playing golf. Woo, boy howdy, now I've heard everything. What's next, cop eating a donut?