11:59:19 F/E: 190
11:59:27 F/E: 210
11:59:28 Captain: TOGA!
11:59:31 F/E: 220
11:59:34 F/E: 230
Very interesting !
That would be 15s from 190 kph to 230 kph.
That's an eternity.
and that with TOGA thrust.
Definitely something wrong here.
Stuck brakes would indeed create a strong Nose Down moment as long as they were on concrete. Only after getting on the grass and 'jumping' a bit downhill, the Nose of the Aircraft starts to rotate. Given the fact that the factor of adhesion would be very much reduced at that moment and considering the bounce after the bump when leaving the runway a subsequent rotation seems plausible.
The story with the breaks seems to match most of the known.
A Nose Heavy CG would also match many of the facts but the acceleration with TOGA thrust should rather have been higher in that case.