(The sole known exception is not a good data point, as it involves one Klingon using another Klingon's sentence as the first sentence in a sentence-as-object construction. It may be that in such a case not having something there is too much. We don't know how this exception works, so it's dangerous to base our understanding on it.
Out of curiosity, do you mind quoting that exception?
In Star Trek VI, one of the military officers says
something, then Azetbur says 'e' neHbe' vavoy That
isn't what my father wanted, literally, Daddy didn't want
that.
-- SuStel http://trimboli.name