How to check who triggered crash when vmcore doesn't have userspace data

Issue

• System crashed with manual crash, but no clue who triggered it
• vmcore generated has limited data and it doesn't show userspace details

...
       PANIC: "SysRq : Trigger a crashdump"
         PID: 19125
     COMMAND: "bash"
...

crash> ps -p 19125
PID: 0      TASK: ffffffff80319b60  CPU: 0   COMMAND: "swapper"
 PID: 1      TASK: ffff8101700ad7a0  CPU: 1   COMMAND: "init"
  PID: 18174  TASK: ffff815ff9a37040  CPU: 40  COMMAND: "sshd"
   PID: 18915  TASK: ffff811fdd237820  CPU: 0   COMMAND: "sshd"
    PID: 19086  TASK: ffff811fdedd4080  CPU: 0   COMMAND: "sshd"
     PID: 19087  TASK: ffff811ff7950100  CPU: 4   COMMAND: "bash"
      PID: 19123  TASK: ffff811fce920820  CPU: 40  COMMAND: "sudo"
       PID: 19124  TASK: ffff811fdc94f100  CPU: 0   COMMAND: "su"
        PID: 19125  TASK: ffff811fe93c07e0  CPU: 2   COMMAND: "bash"

crash> ps -a 19087
PID: 19087  TASK: ffff811ff7950100  CPU: 4   COMMAND: "bash"
ps: cannot access user stack address: 7fffa4f72eb8