Why would you do it like so? Use the QNAP Surveillance Station! It records perfectly fine 4 of my cameras when they issue an alarm. I do not see why would I save directly from 4 or less cameras to QNAP if it comes with decent program doing the job for up to 4 cameras for free and I can watch and search all my cameras on two TVs via HDMI?
I do not know if anyhting changes with different fw versions of the cameras, but I have described in detail how things work perfectly well without formatting disks in the post
Solving some NFS issues on Hikvision cameras. For me, nothing changed in last 2 years.
I have used that same method for saving to my current NAS which is QNAP TS-253A as I described for Asustor NAS.. On QNAP - Made a folder: /Kamere/Balkon (all my cameras are recorded in the folder /Kamere, each has its own subfolder and user), create the user Balkon with 30 gb quota, create the network share /23Balkon (pointing it to /Kamere/Balkon) and give rw rights to the user Balkon (and others as needed). Then on the camera (e.g. Web interface), point it to NAS IP address, folder /23Balkon (entering / and not \), SMB/CIFS, test, save, change to the previous tab, select your new disk (you may see entire disk capacty now but should see 30gb and Unformatted), format, you will now see 30 gb, and save. And that is it. If not, delete contents of /23Balkon and repeat the process.
I use this method only for cameras over my QNAP 4 free licence limit. I have been test saving to folders at USB3 disk connected to my giga router (but that should never be done in normal usage as it is quite likely this data will get lost).