Stocking the goat medicine cabinet is good!
Be sure to research the proper dosage for all the meds you get. Good luck finding the di-methox

sadly it is pretty much on back order everywhere. There was a huge shortage a while back ( might have been in 2015- it's been a while!) and I haven't been able to find it online or local. I was just looking for some for a client and still couldn't find it.
Research all you can. Having the right eye and knowing when to give the proper meds (under a vets supervision) is something you generally learn after having goats for a while. Waiting to treat until you see symptoms of cocci can be deadly. They don't always scour, but when they do you won't have much time. Sometimes irreversible damage has already been done, sometime a big die off of cocci kills the goat, sometimes the intestinal lining is expelled, sometimes they recover, other times they don't.
This is why I like the fecal analysis.
You are less likely to come home to a dead goat. Treating at the right times before they act sick can doesn't put as much stress on the goat. When the goats immune system isn't so stressed from things like cocci, it is less prone to secondary issues.
I know of someone's wether that got a bad case of cocci this year, right after that the goat almost died of secondary issues due to a lowered immune system.
You saw how fast you other goat went down, you had no time. This isn't to criticize you, this is looking at how fast things can go downhill.
Maybe I'm more proactive than others, but I don't like waiting until a goat is on deaths door.
Good luck with your other girl

Please keep us posted