Not meaningless, as Zubr's words later indicate that this murder was committed by conspirators.
It says "apparently," so it's just the simplest explanation for this clue. Which doesn't speak to its accuracy. But, indeed, it could mean that Magnus was not killed by a werewolf or a demonologist, but specifically by conspirators. Both possibilities should be considered.
So you fall at his feet hes the one who betrays you
Its the servants devotion for the decay
Stand up
There are no flowers on your grave
There are no chains
There I keep chanting for the forgotten name © Amorphis