That didn't seem to delete all the duplicates. Some have offset locations by a few millimeters.

Removed 46 more:
osm.org/changeset/157866171

Also, removing the cameras from the first changeset removed my edit and left the old version here:
osm.org/node/12241502270/history
osm.org/node/12244198944

For some reason Every Door has reuploaded the cameras I added in osm.org/changeset/157718299. Seems like reverting either one of these changesets would cause some real cameras to be removed too though.

Did you intend to use building:flats? That is for specifying the amount of flats a building has. For entrances you are probably looking for addr:flats instead.

osm.org/node/11878556663
osm.wiki/Key:building:flats
osm.wiki/Key:addr:flats

Man šķiet, ka tu nokomentēji uz nepareizā changeset :D