I see in the logs you are getting DFCO when letting off at lower RPM <2000, but not from high RPM like ~4500. You are meeting all the criteria for DFCO, but may not be meeting the negative engine brake torque, as that is the only difference is see when it works and when it does not.
You have your RPM axis modified slightly on your tables, but your driver demand is actually comanding higher torque than stock durring decel. I suggest modifing this a bit to ensure it targets a lower engine torque on decel.
My suggested change
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Your DD compared to stock
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What I am seeing
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