From what I know, I would expect that no one has performed a similar experiment to what you propose. Sequencing a genome is still rather expensive and inaccurate. Some parts of the DNA can’t be sequenced at all and most methods still rely on comparing the sequencing reads to a reference genome, making these kinds of predictions harder.
Getting snapshots of an epigenome (chromatine modifications, transcription factors) to the accuracy that you can detect a notable difference after a few years is even harder.
Also, by analyzing the genome of a given somatic cell, the cell is being destroyed and not available to test it again after a couple of years to see if relevant mutations occurred.
In short: Sinclair‘s predictions are probably hard to verify at this point.