Following instructions on this forum, I have just installed a 2013 OBC in my 2012 Miev to reduce the chances of having the same failure again. Has been working fine for 3 weeks (2000km). Behaves exactly as it should.
As you mention, I don’t know if the dealer would have replaced my obc because the fuse was not blown. It would not charge on level 2 chargers and most level 1 chargers. Only on the Mitsubishi charger.
From what I found, on board chargers from 2013 to 2016 would fit. You will need to modify the coolant hose between obc and inverter and « transplant » the high voltage connector and the 12v connector.