It is an interesting crisis Vic finds himself in.
Because if he is a dragonborn, then it means Akatosh exists. And if Akatosh exists, then that means the Godhead exists. And if the Godhead exists, that means that Vic is a part of its dream. And that gets to the tricky part, where Vic realises he might not actually exist.
The only thing I could see giving him any hope of being a real being, is that the ROB just made him a dragonborn, without actually making him suffer all the consequences of being one.