You can delete an entry (as you apparently figured out) and you can turn it into a comment. Just open the .mis file with a text editor and add a colon to each of the lines in the entry (just to be sure - I don't know which it is safe to edit).
Also, of course, you can temporarily remove a location by making it disappear a moment after appearing (for example making it appear on 1st of February, 00:00, and having it vanish on the same date, on 00:01, or even 00:00). Lots of possibilities

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