Underline mine.Official Rulings Digest #111 wrote:1) The question has arisen whether the previous understanding of the interaction of Marvels Told & Voices of Malice with The Witch-King of Angmar is correct. In light of digest 110's ruling on the interaction of nazgul events and certain event-cancelers, we are making the following ruling:
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If the Witch-King is tapped in response to the play of Marvels Told or Voices of Malice, then it will resolve before MT/VoM and thus be unaffected by them. If, by contrast, MT/VoM is played in response to the tapping of the Witch-King, then MT/VoM will resolve first, and discard (and thereby cancel, since it has not resolved yet) the event.
Note that Ancient Secrets does not work in the same way because it can only target permanent events.
It is true that unlike other Nazgûls tapped the Witch-King of Angmar does not become short-event, but long-event. However it is not yet enough to target it with Marvels Told.
This diference merely removes one issue. Second issue is that tapped the Witch-King of Angmar is just declared Long-Event and Marvels Told, unlike Twilight, cannot target unresolved cards, declared in the same chain of effects.