You can possibly blow it up if you short two pins with the meter probe. Best if you have a mating connector and a safe way to probe the wires. Put the black meter probe on the main battery black wire. That's ground on most systems and the reference for the other voltages.
First I would leave the controller disconnected from the battery (no risk of blowing up anything) and put the meter in ohms to see if one of the pins is connected to the battery negative wire. One of them should be near zero ohms.
With power on, measure each pin and look at the voltage readings. Once we have that, we can go from there.
I have never worked on this model of ESC, so a lot of testing has to substitute for experience.
"One test is worth a thousand opinions"