119 timing chain question

[J. M. van Swaay]

I have been reading lots of posts on the 119 timing chain. I am considering the purchase of a salvage E420. The seller reports engine noise and advises that the chain has "slipped" on the right side. The engine will run, but makes lots of noise. Is it possible that the chain has indeed "slipped" or is it more likely that guides/tensioner are broken. Also, if the chain has indeed "slipped" would the resulting shift in valve timing likely result in piston/valve contact. Recall, the engine will run......

I think I have to assume bent valves and possibly damaged pistons/cylinder.....just trying to determine max risk...

I've never seen the 8 cylinder engine opened up. (My limited experience is with the inline 6) Any comments would be appreciated.