HDD Files are unviewable

Hey all,

I have had an external HDD 1TB connected to my windows 10 PC for a few days now and a folder containing nearly 600Gb of info has vanished overnight. The drive is still showing up as almost full.

I have looked at the properties of all folders to view size to make sure I didn't accidentally move the folder into another. All folders only add up to approximately 100Gb. This includes hidden folders.

I have checked the HDDs recycle bin, nothing. I have tried the CMD recovery
:attrib -h -r -s /s /d g:*.*
This recovered some deleted files. But files I had actually deleted a while ago. Not the huge folder I am looking for.

I've run the HDD through Linux and nothing, I've booted it on my Mac and still nothing. Only the same folders I can actually see everywhere.

As a last resort I ran a data recovery tool (Recuva) and an hour later. Just some random data clusters I don't need.

Kinda wracking my brain on this one.

Is it possible that Windows 10 has detected something it didn't like in this folder and hidden it from me? Or am I being paranoid :p I really need this folder back.