Zapphod Beblebrox
Inventor of the Pan Galactic Gargle Blaster
My biggest concern with the 88 landing on contaminated runways are the thrust reversers. Not only are they notorious for coming out asymmetrically, above 1.3 EPR it'll blank the rudder. Additionally, on the landing rollout you have to develop a cross scan between keeping the airplane on the centerline and looking at your EPR and/or N1 gauges to see what in the world the each reverser are up to. Landing is the reversers split to get equal EPR settings are common. They truly are like a box of chocolate, you'll never know what you're gonna get. Pull reversers with similar force on two different airplanes one airplane you barely crack the buckets the other airplane you're rapidly approaching or exceeding EPR limit. Taming 88 reversers is a skill that takes a while to acquire. A Captain once joked "When you figure it out give me a call".
A full investigation will undoubtedly determine the cause but when I heard the plane went off the side of the runway those reversers were the first thing that popped in my mind.
I will second that. Looking at the video a few posts back you can see the nose gear hard over on a dry runway and the aircraft tracking straight ahead. Once the nose gear is centered up the takeoff is continued. If that is how the aircraft tracks on a dry runway imagine a contaminated one.
Now add the thrust reverser element as described in a previous post and you have a recipe for real directional control problems on landing.