@Second_Coming thanks for the push to RTFM more diligently. I revisited the relevant steps and routed things correctly.
I think I was trying to avoid too much un-channeling/re-channeling of the cables, maybe because of the bother that messing with the wifi antenna cables was back when I got the laptop (DIY - had to install the WLAN adapter).
The bulge is still there, but now doesnt’ depend on lid position and pressing lightly on it it gives way, so looks like no pressure on anything inside. I suppose things got permanently bent a bit, even the edge of the top cover’s aluminum has a very slight kink to it in that area. Hope the new top cover will be more resistant to deformation.