You really don’t have to do massive mental gymnastics though.
They could simply say that when you play out the recording for 20 more seconds, it turns into some kinky sex thing they do, or where she says “fecking stop now Mason. I don’t find this funny” and he apologises profusely for taking a daft sex play too far. There’s some pretty easy explanations to make it much much milder than what it is today, so let’s not pretend that that’s completely impossible as you and many are.
My guess is, this is likely the explanation they gave to Arnold, when he talks about it “being part of a longer recording”.
Arnold didn’t actually get to listen to the recording though it appears, so we have no idea if it was true or just cooked up to make it milder for the internal investigation.
If they were to come out with this explanation and then also say the photos had nothing to do with Mason, but all to do with her being jealous or angry and using pics out of context, she would face massive wrath from many Manchester United fans & she would also be accused of doing real damage to the women’s movement of protection for domestic violence victims, being classed “another one who cried wolf”. She just cannot come out of any alternative explanation looking anything but horrendous and possibly in legal trouble.
So when people are demanding an alternative explanation, it’s a ridiculous thing to demand.