So, Renault are 'not disputing the allegations' that this accident of Nelson Piquet Jr at the 2008 Singapore Grand Prix was actually a deliberate move forced upon the Brazilian driver in order for his team mate (Fernando Alonso) to benefit from safety car deployment.

It has to be said, it does look unlike a regular F1 accident, a smooth arc of a slide around and into the barrier appears just plain wrong without previous contact.
If this is proved true it is easily the most outrageous breach of sportsmanship ever known in motorsport. To instruct a driver to crash in any way is putting more than just one person in huge danger and is barely believable.