I just did some research on the resolvconf package as I was not familiar with it.
There is some information here:
and the man page is here:
It appears that the sole purpose of that program is to re-write the resolv.conf based on what interfaces are present on your computer, so this would NOT work for your situation. The only thing that resolvconf would do is deal with situations when you have multiple programs that tend to configure resolv.conf - perhaps you run two dhcpclient programs (one for each interface) and perhaps you also have ppp running to support your connection to the Internet.
The only configuration for resolvconf seems to be the interface-order file. If you look at the man page here:
You can see that it only supports interface name and not domain name in order to choose which name server to use.