User blog comment:BlackDragonKid/BDK's Canonical Death Scene./@comment-30921738-20171101143123/@comment-26863232-20171105192833

It means

'true in that universe'

in our case.

Like, you can have a headcannon about AJ where the Alphas are evil, but in actual AJ cannon, the Alphas are good,

So, HERE, it means that BDK dies from poison in the actual BDK world.