DNS Leak when using HTTPS DNS Proxy with PBR

Hi,

I'm facing DNS leak when using Policy Based Routes (PBR) with https-dns-proxy.

I was intended to pass all DNS requests over the VPN Tunnel and for that I configured PBR to redirect the DNS requests (Google DNS and Cloudflare) to the VPN interface:

In Firewall I blocked all possible DNS requests coming from clients and going directly to the DNS Resolvers.

When I try traceroute to the DNS servers from clients, the route is passing through the VPN Interface. The same occurs when I do it on the router via SSH.

However, when I enter on DNS Leak Test or IP Leak, they are showing my DNS Server coming from my own country and my VPN Interface is connected in a distant country.

Apparently, HTTPS DNS Proxy requests are not passing through the VPN Interface.

My intention for DNS is:

Client -> OpenWRT -> HTTPS-DNS-Proxy (DoH) -> VPN -> DNS Resolver

Apparently this is happening:

Client -> OpenWRT -> HTTPS-DNS-Proxy (DoH) -> DNS Resolver

Any idea to solve this?

My Firewall rules for DNS: