I tend to be preachy about verapamil, it's a drug that creates lot of heart problems. Anyone who is on it, needs a checkup (heartfilm) every time dose changes by 80mg or more. This is the official guideline but many doctors skip it. 240mg is a normal dose for someone with heart issues. Since we do not, 240mg is a bit high. But clusterheads have survived from 1000mg daily or more, myself included, with a heart failure though. I personally would recommend to try alternative safer things first, not simultaneously with verapamil, but that's just me.
Did you read this article already ? https://vitamindwiki.com/Cluster+headaches+substantially+reduced+by+10,000+IU+of+Vitamin+D+in+80+percent+of+people - there's a chart (labeled Update Jan 2017) that should be more simple. Some people who start vitamin D as en emergency only take Vitamin D (for an examply 10,000IU per day) and Vitamin K-2. Then they will do complete regimen when they have blood work done. It's important to check the Vitamin D levels with a blood test.
The Psilocybin and LSD page I linked really covers the mushroom and seeds part. It's good to read completely over time, since you must not "just" take these substances but also learn what you are doing. Psilocybin mushroom is the kind we need or seeds that contain LSA (often called Rivea Corymbosa or RC seeds or ololiuqui seeds). Mushrooms is more of a "trip", seeds is more of a nausea.
Here in Finland it depends a lot of the doctor what they think about Vitamin D although it should not really be a matter of opinion. Some recommend it, some forbid it. Doctors are unable to recommend psilocybin and I think many do not know about the subject at all unless they are linked to patient communities. There may be judgemental views too.
I think the decisions made in the beginning will have a huge impact on the forecast what cluster headache will be later in life. Too few find all the options available to be able to make the best decisions. I wish you all the best and pain free life for your wife as soon as possible.