I would imagine there would be a Post Mortem ( if I was in the parents' position I would request one)
There's the question about neck injury when he was released from his hanging site
Any if they were able to see the damage to his brain stem and the coning they might accept that the damage was done a long while ago annd there was really no chance of him opening his eyes let alone leading anything that would be classed as a viable life .
There are loads of 'not quite adding up'
The ligature - was it a bag tie or a dressing gown cord ? (Both have been mentioned)
Was she in the house charging and phoning. Or as in one report , came home to find him ( hence the was it the 3 minutes/40 minutes)
The level of detail about the rabbit
Examination of his phone will show if he was filming ( which if it was an online challenge , you'd think he would be)
Hollie stated he was anxious and had phone calls from school but she said she spoke to him and it was more an "Arch stop mucking about" type of outcome
He was waiting on a new coat to arrive 
And he'd done the 'hold your beath till you pass out' challenges ( you;d start breathing again though unless there was an obstruction ?)
If . (and at the moment theres no evidence he tried to take his own life , but it does seem more likely TBH) he attempted to take his own life , that is not a crime . But it would be investigated .
It would be so very difficult for her to accept that her son had taken his own life but she must have some suspicion in the back of her mind ? To accept that he wasn't as happy as she thought or as joined at the hip close that she thought ?
Maybe she feels with his religious beliefs ( again lots of speculation as this was brought up after he was injured ) he wouldn't do this ?
And ( IMO ,) she wants him to die of natural cause - cardiac arrest- at his own hand , his body giving up . Rather than someone giving the consent to switch off ( in her view murder / execute him)
His online name was an odd choice for a 12yo .