The EGR malfunction is clearly the cause of your NOx problem. It takes time for the engine to reach the operating parameters required for it to set a code. Most trouble codes require two or more failures before causing a code to set.
I couldn't copy the charts I was going to post. Their owner has them embedded and protected from copying.
HC is unburnt, raw fuel. CO is poorly burnt fuel. HC seems to be your big problem, the O2 code may actually be telling you something.
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