I'm fairly sure it's an offence to film someone having sex without their consent. There are various other potential charges available to the CPS regarding that night.
Filming without consent is voyeurism. In this case it is my understanding that they did not manage to film successfully. They did, however, see what was going on which would still be voyeurism. Assuming no previous convictions they would receive a community order. It is unlikely that they would have gone on the sex offenders register for this offence.
Convictions for voyeurism remain on the DBS record forever. However, it is up to individual employers to decide whether or not the conviction is relevant and should bar the individual from working in a particular post. My understanding is that voyeurism against a child is an automatic bar from teaching but voyeurism against an adult is not.
So if filming a person having sex in a private bedroom without their consent is an offence, then people helping to set that up and / or join in with that would also be committing an offence? Isn't that perhaps a thing called conspiracy?
Possibly but it may be hard to get a conviction and, as with attempted voyeurism, they would have almost certainly have received a community order and not gone on the sex offenders register.
Not placing CM's statement into evidence - if that's what happened - what's that all about
Since the prosecution again went for the line that the victim was too drunk to consent McDonald's statement did not help them. Indeed, since he maintains that she was not that drunk, it would be more likely to hinder than help. I'm not sure what significance you attach to McDonald's statement. I may have missed something but my understanding is that it was largely consistent with Evans' statement.
Even if both witnesses were 100% telling the truth, having sex 'doggy style' and saying 'go harder'
The Court of Appeal judgement does not lay out the similarities in full. My understanding is that they went significantly beyond that. Indeed, I doubt a jury would be persuaded that someone wanting sex doggy style and asking their partner to go harder was in any way unusual enough to be convincing as evidence of consent.