Yes, Cracknell looks like he's jeopodised the success of the team.
And given his foot injuries and infection and pneunomia on one lung I was very surprised that the Dr. gave him a 50 / 50 chance of continuing.
I reckon that Ed & Fogle should complete it as pair and learn from what happened to Cracknell; although I don't think that either of them are stupid / arrogant enough to think that they would do what he did.