The difficult kind of off-roading should never be attempted by the inexperienced, or those who have only driven a car on the road. Purpose-built off-roaders, such as the 1980s version of the G-Class are super-capable, and almost nothing can stop them, except a really steep hill, with a sheer edge.
inexperienced ‘adventurers’ try to tackle a hill which should have better been left alone, or tackled using a winch, otherwise, the risk of toppling over would have been much too great to even think of attempting the climb. Now, as these things usually go, the Merc does topple over backwards, virtually totaling it - it can be repaired, but it is questionable whether it is worth it or not, as the hill was quite steep and and high at the same time - not a good combination.
They should have just left it alone and tried a different route.