They're a big accounting firm based in the UK. They tend to be more involved with consulting/advising/auditing the financial matters of a business rather than market speculation. Their clients are usually large businesses and corporations.
They are accounting firms, so their definition of blockchain expert may be a little different from what we know. It could be that to them, "blockchain experts" are those who have knowledge on how blockchain works, its intricacies but do not necessarily need to be a coder or developer. Though I agree that "Expert" here is an oversell.