Wurt being unable to trade with the pig king makes sense as she doesn't like pigs, but I think the option should still be there, just at a cost. I think that Wurt should be able to trade with the pig king, but lose some sanity upon doing so, as well as having her say "only because I have too..." or something similar. Another idea is to maybe give Wurt less gold for trinkets given to the pig king given their apparent hatred to the mermfolk.