VPN on Router and another VPN Client on Computer

I'm using NordVPN on my router (Flint 2). I don't have any leaks (at least to my knowledge). A while ago I asked the Gl.iNet support what the right DNS settings are. I wanted that my computer only uses the VPN DNS. I just wanted to make sure that my real IP-Adress or dns is not leaking in any shape or form.

The support responded: "Please select override all clients, then all devices include this router will use the VPN DNS as outgoing DNS and you can see the result of DNS leak test. Only VPN DNS servers are shown."

and

"Some devices like notebooks, PC, you can set them to use their own DNS servers. With this override function, then no matter what settings are on the devices, it must follow the router's DNS settings"

I was satisfied with that answer. So I enabled (as instructed) "Override DNS Settings of All Clients". I also enabled "Block non VPN traffic".

But since then NordVPN has been blocked by a lot of services. I can't even use reddit or youtube a lot of the times. I have to switch servers a lot, to finally get a working one. I found out about MysteriumVPN which is a decentralized VPN so you get a real residential IP. I already tested it with my real router (the one from my ISP) and it works great! You can't install them on a router level though.

I want to use NordVPN on my Flint and then connect to MysteriumVPN on my Computer. In case MysteriumVPN leaks anything (killswitch fails, DNS, WebRTC or similiar) I want that only the NordVPN IP Adress or DNS servers are leaked. What are the correct settings? Most importantly: If I keep "Override DNS Settings of All Clients" enabled are there any issues? Like for example will my Flint force the MysteriumVPN DNS to be overwritten?

If I disable "Override DNS Settings of All Clients", but keep "Block non VPN" enabled is it less safer then before? Is an DNS leak more likely?

Thank you so much!

Hello,

This perhaps is not a perfect way. Look, if there is a problem with the NordVPN connection (such as unable to access reddit or YouTube), in this case, is the MysteriumVPN available to access them?