LTC4380-4 Clamping Simulation

I am using the -4 in a simulation, as I want to have the auto-restart function.  But I am not seeing this behavior in the simulation.  Here my nominal voltage is 12V, but can accept 21.5V Max.  I limited Vin to 12V because 12 + 13.5 - 4 = 21.5V.   When I add a load onto the simulation, I run into problems.  The output shuts down and never recovers to 12V.   Is auto-restart simply not capable of simulation.