Mode 6 is ignored by the EC2 in the versions compatible with the EM2.  They have the manifold pressure ignition control that advances timing at low MAP and retards it during boost.  

So Todd, can you confirm that you were using the chips that came with your EM-2 when you detonated your engine?  If so, the timing retard alone would appear to not be enough to stop the damage.  

Rusty