I think I found it. The problem appears to be with locations where I have 2 inlets located in a sump. One of these inlet is a backup for clogging, so I am only assigning flow to one of the inlets for modeling purposes. The problem appears to be that the drainage area flow was assigned to the downstream inlet of the pair. If I create a profile from the network outlet to the downstream inlet of the sump pair, the HGL/EGL plot fine. When I extend the profile to the upstream inlet of the pair, the HGL/EGL are calculated but not plotted.
So now I've reassigned the area flow to the upstream inlet of the sump pair, and created profiles from the outlet to the upstream inlet, and the grade lines plot as expected. There is no reason the grade lines should not plot both scenarios (i.e. flow assigned to downstream or upstream inlet in the sump pair). If there is no flow in the upstream inlet, the HGL should just stop plotting at the downstream inlet.
So now I've reassigned the area flow to the upstream inlet of the sump pair, and created profiles from the outlet to the upstream inlet, and the grade lines plot as expected. There is no reason the grade lines should not plot both scenarios (i.e. flow assigned to downstream or upstream inlet in the sump pair). If there is no flow in the upstream inlet, the HGL should just stop plotting at the downstream inlet.