I'm glad it's working!
Not trying to convince you to use it, I just find the stuff interesting. I wouldn't want you to using something you don't feel confident in using.
Just a bit more about Diatomaceous Earth. It's just really small "sharp" dirt (ancient shells, etc). As long as you use food grade or animal safe it should be perfectly fine. The stuff they use on crops is industrial and may have contaminants, so wouldn't be recommended.
They actually use the food grade (or animal safe) in animal feed. It's totally safe for everything except some reptiles and any insect with an exoskeleton.
https://www.dicalite.com/2017/10/three-ways-to-use-industrial-minerals-on-the-farm/
The way it works is that it's so small and sharp that it sticks to them and cuts through their exoskeleton and dehydrates them. There is no mechanism for this to cause damage to mammals, aside from possibly breathing the industrial kind.
https://progressiveplanet.com/is-diatomaceous-earth-safe-for-all-animals/
Again, I just find it interesting. I'm glad you found a solution that is working!