Originally Posted by
andrewwm
Did you try doing a multi-city search (CPH-LHR, LHR-HNL, HNL-CPH)? I did this on Hipmunk and it gave me a bookable fare for the dates I wanted, although it was about $100 more than the advertised fare.
This is actually a good tip, because you can use the ITA routing language to force it book an SK flight number as opposed to a codeshare. United.com, for all its faults, seems perfectly happy to accept these fare constructions fed to it by HipMunk.