A fenestron type tail rotor is not new to Bell, they dabbled about ten years ago with a 'ring tail' on the 400 [a pre-427 twin]. It was minimalist and probably did little more than mark and guard the outer tail rotor. They dropped it and the 400.
Bell did produce some pictures of a new project using a 'proper' fenestron at HAI - potentially a 206 replacement. It was described as a Gazelle lookalike and that was a fair description.