Thanks for your response. I read something similar on GMauthority but they mentioned the diesel not fitting, not the 6.2.
"While the new fascia looks great and comes with a higher approach angle, adding to the AT4’s off-road worthiness, it also obstructs the intercooler and intercooler piping needed for the new 3.0L I-6 LM2 Duramax turbodiesel engine. Thus, the engine will not be offered on the AT4 trim level."