Happygardener,
I happened to be off work due to being restructured from the bank I was working for when all this happened to me, so not sure if you need to be off work yet or not.
It does not hurt to apply as the worst that could happen is they work take money off the CPP each month from work earnings.
I would call Service Canada for advice, as ALS is terminal, your husband would get approved right away.
Try to keep the emotion out of it and treat it as a business transaction. We pay into it, we are entitled to it.
The other thing is if you are connected to a ALS centre in NS they would have access to a social worker devoted to answer any questions you guys have.
Good luck.
Casey