I suppose that solution will work if the container provides OMV with the information it needs through port 53. Otherwise something will not go quite right. Since I don't know what those containers do I can't say if that solution is still valid.
This is just a "bypass" solution for the port 53 being in use by the host. It binds the host port to the container.
See it as a volume like:
It won't damage anything.
I guess if you're saying this it's because it works for you
I don't use neither adguardhome nor pihole on my home.
Don't have any use to it since my browser's have the adguard extension activated (yes, I use M$ and the Edge browser) and it blocks most of what I want/need.
And having it as DNS on the router, breaks my ISP TV boxes, (although maybe due to me not giving too much tought or attempts to sort it out)
Don't get me wrong, I'm not saying that solution doesn't work, but maybe it's not a universal solution.
It works OOB on any container that requires port 53.
It's not perfect, but it works for newbies and doesn't require to be a "rocket scientist"
Like I said prior, once people get more used to docker, then VLAN is the way to go, for sure.