Your husband should definitely pursue legal action. This kind of behavior needs to be so dramatically economically dangerous, so that companies will stop it. In a perfect world people would be good to each other, but things being the way they are, they can use a tough lesson.
As far as work a blind person can do from home, it really depends on your skills. Don't look for work that can be accommodated, instead look for remote positions that anybody else could apply to. Ideally, he wouldn't even mention his disability until the onboarding process.
Here are a few fields to consider: copy writing, editing, language services, like translation and localization, software development, sales, call center work, etc. In fact, he could start freelancing, while figuring things out with his current company.
When looking at job listings, it's always worth checking for a note on accommodating disabled workers. It could be virtue signaling, but it's always a good sign.
As far as certifications for accessibility testing, you can only get certified after a number of years in the industry. You can, however, get quality training for free, through
$1. You'll want to know some HTML, CSS and JavaScript for some of the courses, but anybody can get a lot out of this training.
I'm also gonna let you in on a little secret: instead of having the company pay for JAWS, he can load up
$1 on a USB drive for free and learn it at home.
Ultimately, you don't want to be working for a monster who resents you for winning in court, so I'd suggest the two pronged strategy of taking legal action and looking for a better job, at the same time.
One more thing: this is directed at you, not your wife. You can use Reddit. You can use your computer and your phone, you can go grocery shopping on your own, and you can use a white cane and get orientation and mobility training. Your wife sounds like a great lady and marriage is all about supporting each other, but I want you to take charge of this situation and all the other ones. We'll be here to welcome you with open arms, fight along side you and push the metaphorical darkness away, as independent equals, never as needy or helpless individuals.