The parameters of MAiD have changed now since my own father died. He had to be of sound mind RIGHT up to the minute before they gave him the injections, they asked him. That meant I had to keep him "with us" until that moment which was awful. He wanted this option so badly and managed to have 5 hours of perfectly cognicent conversations to say goodbye to everyone the evening before his scheduled assisted end. Then the effort exhausted him and he was in and out, terrifying.
Now, I believe, changes to Bill C-7 mean people may use something called a waiver of final consent. That is, a person who has requested assisted dying, been assessed and already found eligible, can make a written arrangement with their medical or nurse practitioner for it to be provided on a specified future date. The procedure can then be provided on or before that date if they lose decision-making capacity.
Anyway, your ex is an utter ass. Again, you cannot "preplan" an assisted end. It does NOT work that way at least here in Ontario. To be eligible for MAiD under Bill C-7, a person must be eligible for government-funded health services, be at least 18 years old, be capable of making decisions with respect to their health, have made a voluntary request for MAiD, and have given informed consent after first being informed of the means available to relieve their suffering.
In addition, a person must have a grievous and irremediable condition, defined as:
1) a "serious and incurable illness, disease or disability;"
2) "an advanced state of irreversible decline in capability;"
3) "that illnesses, disease, or disability, or that state of decline causes them enduring physical or psychological suffering that is intolerable to them and that cannot be relieved under conditions that they consider acceptable."
If a person meets these eligibility criteria and their natural death has become reasonably foreseeable, as long as they still have decision-making capacity, then they are eligible for MAiD.
So, unless your very young healthy boys meet these criteria, they can't "set it up." Neither can your Ex for that matter!!