Shivambu told ANC MPs that President Jacob Zuma was going to kill them if they stood against him as political opponents.
The former public service and administration minister is the fourth axed Cabinet member to quit Parliament.
Pettersson was replaced by Mmamoloko Kubayi when President Jacob Zuma reshuffled his Cabinet last Thursday.
On Tuesday, the premier bemoaned the reaction to "her statement of fact".
A defiant Andile Lungisa has until Thursday to resign from his ANC regional leadership position, or face the consequences.
North Gauteng director of public prosecutions Advocate Sibongile Mzinyathi will also not be suspended.
The SABC has blamed losses in the past financial year on events of national interest that were not budgeted for.
Opposition parties criticised Dlamini for being negligent and unprepared, during a meeting to detail the department’s plans regarding grant payments.
The Democratic Alliance leader says scenes from Thursday’s State of the Nation address were a glimpse of the future under the ruling party.
The assembly on Cape Town’s Grand Parade will focus on the ANC’s views of radical transformation