Maxwell and Aloxius know.
Jacen’s original suicide note was supposed to be deleted by the Guard of Iron. A rather bitter Manswell — Elga, the grandmother of Helga Manswell — made a copy in case she ever felt the need to topple the High Lords.
Richard Manswell knows all about it. He has his own plans for using the information … and has no idea it has been copied and that anyone else knows.
As to how it was copied….well, Elga Manswell went missing nine years after Jacen’s death, when she was on a long-term mission to scout new colony worlds (she refused to sit at home looking pretty).
Dun dun dun.
Purge the alien. Kill the heretic. Suffer not the witch to live.