There is no doubt in my mind at all that Johnson wants a no deal outcome. The issue with that is that the Benn Act (almost certainly) stops that, so Plan B for him is to save his own neck by getting a deal over the line. Johnson cares about Johnson, no one else.
He's challenging the DUP and the ERG to take a Brexit as opposed to the Brexit they wanted.
In essence, it's May's Withdrawal Agreement all over again, but with the added impetus of a ticking clock on the Brexiteers, who really are now risking no Brexit at all.