They're in continuity technically. They are just noticeably contradicted by other events. Ewing actually makes a reference to LT being reborn in Ultimates, which is clearly a reference to what Starlin wrote. It can be argued that the LT killed by Order/Chaos is the Warlock/LT.
In Ultimates #11 Thanos says, "Beautiful Death, to whom I once devoted my all. Perhaps somewhere, in the endless halls of being, some aspect of me is at her side..Content at last. Or perhaps THAT story, ended with the incursions." Possibly meaning that if the graphic novels happened, it was before the Secret Wars.
So I think that Ewing is a big continuity person and this is how he fit the OGN's in continuity!