Thanks. Watching the guide I actually realised the thing I was checking that I thought might be the display connector was actually something else. I can’t actually check the display connector at the moment because I can’t get the bezel to come off. The guide says to slide your fingernail in at the corner but that’s really not working for me because my bezel has no gaps at all anywhere, and I’m worried about damaging it if I do end up having to return it.
Support did get back to me with a nice message proposing a slightly different reset process (basically removing all expansion cards, ssds, ram, power cable and the battery, leave it for 15mins to power down, then put the battery ssds, ram and power cable back in and do the reset process with the button. This unfortunately didn’t seem to do anything in particular.
So the state of play at the moment is I’ve become rather more familiar than I was planning to become with the interior of the thing but I haven’t actually got it booting yet. Still remaining positive though.