I don't think any details have been released as of yet. I know a few years ago he was struggling with diabetes and had to get his legs amputated which was awful news.
Kamala was well before my time, but had such a great run I've seen pieces here and there. He's another one of those Memphis prodigees Lawler saw something in and I believe he designed the face paint and helped Harris come up with some of the mannerisms.
When I look at Kamala, he's a key example of body language and how that can make somebody into an attraction. He wasn't the best athlete or grappler, but the way he moved made him so mesmerising and believable as this heel.
I remember him as a popular opponent for Hogan and as the guy who managed to body-slam Andre in Mid-South.
EDIT: It appears to be Covid-related.