Confirmed here.
The full-length clip is 3 minutes 31.011 seconds long.
The shortened clip is 2 minutes 36.500 seconds long.
That = 0.74167
And 89 bpm / 120 bpm = 0.74167 too
'Tempo match on' caused the length of the clip to be recalculated when the clip contains a tempo map and the 'End' marker is inserted at that point. The following notes are not displayed until the clip end is dragged out.
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It looks like there's a clash between the Media Explorer's "Tempo Match On" and the Import's "Import MIDI Tempo Map ..."
If I untick "Import MIDI Tempo Map ..." then all the notes are displayed.