This is just how your NAS device is functioning.
The presentation of your data storage over the network (as Windows-compatible file shares) is different from what it looks like inside the NAS. And since your Plex server is running directly on the NAS, it looks at it from the inside.
Just point your Plex libraries to those subfolders in /share/CHACHEDEV1_DATA/Public and be done with it.
You might wanna bookmark this: Qnap faq.....read me first!
