there are two things I can see here. One is the issue with the lost drives/lost editing permissions that could be affecting your stuff. I've seen everything happening, from my most common issue of my colleagues not getting the editing permissions (I'm CR it's hard for me to check that myself), whilst myself I've seen lost drives, drives appearing but not the reports, reports appearing but not the drives, etc. But it's been quite stable for the last two or three weeks.
the second one, which I think it's what's happening to you, is that waze ignores camera reports if there is already one nearby, whatever this means. If you deleted every cam but one, your cam report may be ignored because it's too nearby the other one. Of if you deleted everything, it may happen the match is still happening with the deleted ones.
I'd personally suggest that you do both a cam report and a user report, as the user reports should not fail. Then if there is already a cam on the map, just use the report to move it to the right place. Or, honestly, just put the cam more or less where it should be, and just make sure it does overlap the right segment and the red dot is snapped into the segment. The GPS error is big enough, and the warning is early enough to cover some meters.
PS: the multiple cams you saw could have happened because all those users created their own cameras during a short period where no cam existed on the map (the delay of the drives etc.). Or the de-duplication may just kick in as soon as an editor touches one cam. who knows?