Kas was Terran's Chief Magistrate for a short period because nobody else wanted the job. He accidentally moved into Zuma territory and got into a scuffle. He then changed his story from 'an accident' to 'trying to enlist the Zuma to help' and referred to Haktoo as 'almighty,' which as it has a religious context immediately alarmed the entire realm who protested him out of office.
There were plenty of letters going around at that time that could be read as anti-Zuma, but they were anti-Zuma in the sense that 'our ruler should not be sublimating himself to Daemons,' not 'let's all go kill the Zuma.'