I think the WAW issue is limited to BA and (maybe) AY or others who may use/consult BA's rate desk for RTWs (if such is possible or done.) It also appears to be limited to WAW. We're ticketing through IST and BA there agree with the USD-denominated fare that shows up on all the star files (and QF website) that are floating around, so no peculiar cost inflation over the "published" xONEx fares.

My hunch is that for whatever reason, BA at one point converted a "strong" USD dollar into Sterling, then into Zlotych in order to price the tickets. Subsequently the USD tanked, but nobody at BA has bothered to address the issue, so the PLN rate reflects the dollar's previous strength and current weakness, hence the "increase" over the USD ticket that AA/Tal sold Gaza and others.

I suspect that there's just not enough business through WAW to justify BA undoing its decision, and American's relatively inferior transatlantic premium service means anyone planning on going west on their RTW has to choose between higher priced BA tix v. dealing with AA's GSA and having to ride AA as their transatlantic carrier. Idle curiosity leads me to wonder how Tal would be using their CX GSA hat for itineraries going the other direction.