Mrs Meadow-Brook as the Aristocrat

Dr Black and Mrs Meadow-Brook have a long history. Many years ago, her husband died in suspicious circumstances. Rumour has it that she and Black had co-conspired to kill him so that she could claim on his life insurance. Nothing was ever proved, but after that, they went their separate ways. Until the dig. Black had burned through his money, so he reached out to Meadow-Brook to fund the excavation. Perhaps he was blackmailing her, and she decided to put an end to the drain on her resources?