Board Thread:Warhammer 40k General Discussion/@comment-37.152.33.225-20131111163502/@comment-74.128.152.190-20131209230542

We can't know for sure if Russ actually killed them.

The death of Dorn and Alpharius/Omegon are ambiguous at best so there really is no telling if the lost primarchs are, in fact, dead.