Pete was a skinny lad back then wasn't he, seems unlikely he could pick someone up and lift them over a balcony, especially if he had been on the booze/ gear (which was probably extremely likely of that time).
I can understand why the mother of course would want some justice for her son, as from what I've read there doesn't seem like much evidence for him committing suicide. But, also, I don't get why the documentary has been addressed at Doherty? Seems like it's just using his name to get air time/ hits, which is fair enough for her son, he deserves that, but Pete doesn't deserve to be directly pointed at, just because he was at the party. It might have been Pete's "bodyguard" who seems a bit of a gearhead nutter, but were they even in the same room etc? You never know, Pete might have said throw him out the window, back then there would have been a queue of people willing to do whatever he said, not just his "bodyguard".
I'll have to watch the documentary to get a bit more context.