No, disregard that. I think the issue may be that those records are part of the cell grid map for a given worldspace, and even if TES5Edit seems to remove them, CK will add them back (or maybe they're never really gone). TES5Edit is flagging them as ITM because there's no LAND record associated with them; I have no idea if this is intended behavior or not for TES5Edit. However, if you open one of these cells in CK and make any minor landscape edit, it will generate a LAND record and TES5Edit will no longer flag it as ITM (tested).