Can't or Won't? Urgent advice needed

I am a non-ADHD spouse trying to understand and support my ADHD husband. I understand that ADHDers find it hard to do a task unless it is interesting, challenging, or urgent. I have also heard it described as “they can’t” get started until the task becomes one of these three things. Question: How literal is the word “can’t”? How is a spouse to know when an ADHD spouse is unable to accomplish a task and what is to be done about it?

This is our situation:
My husband lost his job due to ADHD symptoms 2-½ months ago. He has yet to submit a single job application, and we will run out of money next week. Besides finding the contact info to a couple places for him, he has flat out refused any help from me. He’s shared that deep down he does not want to find a job, though he knows he should and must. I suspect that his overwhelm has frozen him in place. In light of him refusing help from me, should I respect that refusal even if I suspect he is frozen? Perhaps he’ll snap out of it when the sh** hits the fan and we can’t pay the electric or buy diapers…. Is there ever an appropriate time to do an ADHD version of an “intervention”? I don’t want to just sit by watching him hurt himself and destroying his future if he’s literally unable to help himself…. But how to know when the “won’t” becomes a “can’t”?