Well....
I changed my factory firmware to spark_3 and tested again.
My core went to blinking red --> restart --> not sure if recovery mechanism kicked in --> OTA flash --> solid magenta and hanged
I can only say that if the recovery mechanism is in the compile-server2 to stop user code from running if there's some weird error, it's not working somehow. I have my core repeatedly blinking red --> restart -- runs code again --> blinking red