Mercedes C200 W204 ELV EZS

I have a W204 where the ignition won't turn on. I removed the electronic ignition switch and the electric steering column lock. The locking pin for the steering column lock remained in place during the removal process; otherwise, it wouldn't have been possible to remove them.
After I removed the electronic locking system from the steering column, I reconnected everything to the vehicle, and suddenly the locking pin popped out. If I insert the ignition key now, the locking pin moves inward, and when I remove the key, it moves outward again, and the ignition can be turned on again.

Okay, so my question is, what is likely to be the cause now, either ELV or EZS?
Does anyone know what's going on behind the scenes? Is it similar to what happened with the Passat 3C, where a faulty ELV (Electronic Locking Valve) could prevent the ignition from turning on? You can find both answers online: either the ELV (low-voltage installation) is broken, or the EZS (emergency shut-off system) is broken.