No that is not what it means, it means pfsense will ask itself (default resolve) and maybe 192.168.1.1 - but that is not where unbound will forward too, unless actually set to forward.
So yeah that would explain why pfsense can resolve, but when a client asks it does not.
Depending on what unbound sends back, nx or servfail when it resolves would determine if 192.168.1.1 is even asked, etc..
If he wants pfsense to ask dd-wrt for dns, then he should setup unbound to forward to that.. Then that should either forward for public stuff or resolve on dd-wrt, etc.
if he just wants pfsense to be able to resolve whatever entries he puts on dd-wrt for specific domains, then he could just seutp domain overrides for those domains to point to dd-wrt as the ns for those domains.