Brazilian investment banker André Esteves made one of the best trades of his life on December 18: he swapped a muggy cell in Brazil’s notorious Bangu prison for house arrest at his sprawling São Paulo residence.

But while the 47-year-old billionaire's scenery has improved, his troubles haven't. He has been charged with obstructing Brazil's far-reaching probe into corruption at state oil firm Petróleo Brasileiro and prosecutors say he is being investigated in other matters. He has already lost control of BTG Pactual, a brokerage he built into a dominant Latin American investment bank.