I think it's important to recognize the fact that dying from risky sex play isn't necessarily murder.
Sex play of this type is one of a wide range of risky activities that many people engage in voluntarily. Accidents happen. Deaths do occur. There are many contexts in which a bad actor can make murder look like an accident.
I think it would be very dangerous to find that killing a woman in this way is necessarily murder. I think murder in these circumstances has to be proven the same way as murder in any other circumstances. Not being able to determine whether it's really murder isn't a good excuse to call it murder by default.
I'll point out once again:
There's an extremely significant difference (in both time and effort) between
1) Choking someone into unconsciousness, and
2) Choking someone to death.
As I've also pointed out already, the aim of erotic asphyxiation is to become choked to the point just prior to falling into unconsciousness. If one is choked into unconsciousness, then it's absolutely obvious - to the choker (as well, of course, to the one being choked) - that the choking has gone just a bit too far for it to be effective in terms of heightened sexual arousal. I'd hope you'd understand that this is an absolute given.
And if you do understand that, then you'd also understand that the logical and reasonable thing for the choker to do at this point - assuming he genuinely has an interest in heightening his/her partner's arousal and has no interest in doing him/her any injury - is to release his/her grip from the partner's neck, in order for the partner to regain consciousness quickly.
What the choker does NOT do at that point - the point at which his/her partner falls limp, unconscious, unresponsive, eyes closed - is
maintain his/her grip around the partner's neck for, at the very least, 45 seconds further. But that's precisely what the defendant, by definition, must have done.
In fact, can you point to any rational reason why a choker who a) was assisting a partner in erotic asphyxiation, and b) only had an interest in helping his/her partner attain sexual arousal, and had no interest in harming or injuring the partner....... would carry on choking the partner for a substantial time period after that partner fell into unconsciousness, rather than releasing his/her grip and allowing the partner to regain consciousness?