Vogel was certainly a witness. He once spent several weeks staying with a JW family I knew in Tahiti. He used to walk around the island (so they told me) picking leaves off trees and telling them what it was good for. It is my understanding (that apart from his bread, once well-known in Australia) his products were a mix of homepathic medicines and herbal medicines. They were, as SBF remarked, extremely popular in Germany, as this Bloomberg news item discusses.
https://www.bloomberg.com/news/features/2021-10-12/homeopathy-doesn-t-work-so-why-do-so-many-germans-believe-in-it#:~:text=Roughly%20half%20of%20Germany's%20population,re%20satisfied%20with%20the%20treatment.
The above article also points out that homeopathy is also popular in India, where it is seen as akin to traditional ayurvedic medicine.
To understand the popularity of homeopathy we need to appreciate that it came into use in a time when orthodox medicine was not very advanced either.
But I do appreciate that its popularity in the JW org, is just a minor bit of evidence that the HS did not tell the the FDS that it was going to be superseded by evidence-based scientific medicine.
And as for Alfie Vogel, he did, I understand, finish his life disfellowshipped