Lord and Lady Teviot were the heir hunters, sadly they were unable to find any relatives for the gentleman. In fact because he'd not left a will and had no obvious family, the local authority were going to give him a pauper's funeral. Thankfully, his friends all rallied round and gave the chap a fitting send off.
They might have tried when the estate first came up, the Teviots often chase down smaller estates that the bigger companies don't take up.
I suppose in some way estates going into the government coffers mean that the rest of us benefit in some way