I’ve found maya to do this in the past and its usually down to it not having the ‘renderable’ button checked in the cameras attributes. You may have told the MR render globals which camera to use but the camera itself hasn’t got ‘renderable’ switched on so maya being the clever thing that it is decides “ok I’ll fire out 200frames of black for you” …cheers
give it a quick check. If it is set to renderable - try creating a new camera and put it in the same place then see if it renders with that?
sorry i cant help more - this switching the ‘renderable’ button to OFF is a weird bug I’ve found with maya so thinking it may be your problem?