You got the legit quote from Ruin, but here is a better translation: They take their true death, what can finally end them, and they roll it up into a metaphorical ball, stuff it into a metaphorical cannon, and literally shoot it at people. Toland defined himself a friend to the Deathsinger, and she put him in this cannon of ascendant death.

To quote Ir Anûk and Ir Halak, "A method by which Ascendant souls can be detached and integrated into a tautological and autonomous thanatosphere, which we tentatively term an oversoul. Oversouls can be stored in a throne world as a mechanism of enhanced death resilience. As a side effect, new refinements to our Deathsong may be achieved, moving us closer to a generally effective paracausal death impulse." In simpler terms, they are removing their deaths and hiding them in the Oversoul while simultaneously turning them into a weapons