No, when {{{1}}} == treasure, /journal is guaranteed to exist. We include /journal (NPC) too if it exists. I think it's just the combination of conditionals with transclusions that causes some bug to make them appear in Wanted Pages; I never bothered testing since the fact someone else knew about it when I asked made me think it'd get fixed at some point.
I'll look further into the exact causes of this when I get the time, then, and see if there are any open bug reports for it or anything similar.
(Note for those confused: this is about the subpages listed in Wanted Pages, while the conversation above was about the interwiki links.)