So glad you were able to recover your DS supplies! Funny, I also bought an EHD on Prime day.
I try to remember the
3 2 1 Rule: keep (at least)
3 copies of your files on at least
2 different media and keep
1 copy off-site (for many people that's in The Cloud). Maybe this has been talked about here before, but I just love that strategy.
For me, besides whatever is on my laptop, I currently have:
5 EHDs at home
BackBlaze, which I've had for about 1.5 years and I love it. Hopefully you love it, too!
Amazon Prime Photos for my photos and LOs. It's free for Prime members and super easy to use.
Two about-half-full EHDs at my parents' house. Those are my extra "other location" EHDs. I go there about once a year and add to them. I write down the date I was there so I know roughly what needs to be added. (This is more for photos than for every.single.kit. I've purchased since I was last there. For DS, I back up what I see in a quick glance on my laptop.) They live in another part of the country so having EHDs at their place is another great "physical location."
Anyway, let me say yet again how glad I am you are able to recover you supplies! It must have been such a sinking feeling when you realized you couldn't access the folder.