It's a difficult one. If she consented to it at the time, but then woke up in the morning and thought that it wasn't too great an experience, well that's just tough shit. Decisions have consequences, and you just have to deal with them however unpleasant. If she didn't consent to it at the time, and they went ahead and did it anyway, well that's clearly rape, and he should be banged up and sacked.
Of course there may be mitigating factors in the above (Ie: drink/drugs - and if it's the latter, then that should definitely be on the code of conduct), but we'll have to see what comes out at the trial.
On the basis of what little I know about the case, I would run Ched's defence as follows:
1, Ched, mate and girl get royally pissed.
2. Ched and/or mate say to girl "fancy a 3some"
3. Completely sozzled girl thinks "wow thats hot, yes please"
4. 3some happens
5. Girl wakes up in morning, next to 2 men, with a blinding headaches and has little or no memory of the night before, but it's pretty obvious she has been shagged.
6. Girl thinks,"OMG I would never do this, I must have been raped" and genuinely convinces herself she didn't consent in order to deal with her feelings of guilt/shame etc
7. As girl cannot remember anything about the night before a jury cannot be sure she did not consentr.