At 4:18 of this video titled "Trump's UN Speech Advocates For Both Peace And Nuclear War", Stephen Colbert said:
Now, the most awkward moment had to have been when he brought up Venezuela.
And then he showed a clip of Trump's "most awkward moment" at his UN speech.
I wonder if it has to be had to have been instead of has to have been or must have been.
I'm pretty much sure that you can easily use must have been there without any problem. But I'm not quite sure why Stephen used had to have been instead of has to have been in this context.