[solved] No DNS over VPN

have you tried to use nslookup to query a domain to the unbound ip? doing that you don't need to enable unbound logging...
if your unbound if failing and you are pretty sure that is the root cause of problems then do a firstboot start with a clean system and try again to configure just unbound to see where is the configuration problem is there is any... If not check your hw specs, if you had a slow cpu, little ram and no enough storage may be is that the source of problems.

about:

push "dhcp-option DNS 10.0.0.1"

you should put that on your openvpn config file, and 10.0.0.1 should be the unbound IP from the VPN subnet. check OpenVPN if you need it, but please try the steps marked with asterisk that I previously described first in order to discard problem, read it again on my preovious message.