There could be two Harry's. Kindred could be the original Harry that died and then went on to make a deal with Mephisto to become Kindred. OMD could be part of the deal that Harry made with Mephisto, as a way to mess with Peter even more. It would also help explain why Mephisto would have even been interested in making the deal that he did with Peter, since it's not the type of deal he usually makes.

The Harry that we see as a prisoner could be a new Harry that Mephisto created to mess with Peter as part of his deal with the original Harry (Kindred). This is the Harry that we have been reading about ever since OMD.