Will the summit actually progress towards peace?
If I was trying to make this happen, I would for look for a neutral party that both side respected as a moderator and can ensure adherence to any agreement. Immediately you cross out the US, China, and Russia. The only one that comes to mind is Germany's prime minister Angela Merkel.
A first move forward would be the North removing artillery from the DMZ and the US buy back the THAAD III missile defense shield. That is a tall, VERY TALL order.