I have prepared 100's of expert witness reports - some before and most since I set up my consultancy in 1999. All those related to on-road crashes were single vehicle crashes and 95% related to heavy vehicles. Necessarily many heavy vehicle crashes involve/ result in rollovers so the need is to understand the dynamic models relating to the vehicle movement up to rollover being initiated, rollover, and related to vehicle movements when no longer supported on wheels. Unfortunately in general my involvement was well after each of the incidents. And further in general there were many photographs of the crashed vehicle and the damage to the vehicle but generally very limited photographs of the tire marks on the roads prior to the endpoint of the heavy vehicle. And of course these tire marks are critical in modelling the crash from start to end. So in general my expert reports contained detailed assumptions that are used in preparing the expert report - and these were aimed at ensuring I could model the incident with a high degree of accuracy. And the key factors in this modelling include an understanding of the behaviour of tyres and suspensions and brakes, and the typical behaviour of heavy vehicles in near rollover or rollover situations. For example in Australia and articulate and semitrailer will almost commence rollover from the rear assuming it is legally and heavily loaded. So the critical rollover behaviour that is modelled is the static rollover threshold of the rear triaxle suspension group.
I trust these comments go some way towards satisfying your question.