It reminds me more and more of an old T.V series called
"The Prisoner"
The prisoner is locked in an island. And tries to find the responsible who is
called Number One. At the end it seems that number one is the prisoner himself.
That's the idea, the whole thing is some kind of a dream or twisted reality
that Patrick Jane is responsible for.
So we are looking at two things here:
Jane is Red John or Jane is dreaming the whole reality and he is still in the
mad house.