It should have still entered the keyway, since as far as the pins are concerned, it would be a blank. But have seen the wrong side of a key cut before. Even sent someone a key cut on the wrong side as a gag.
When taking apart my first U-Change lock, I wanted to take apart the key pin assembly so I could see how it worked. The key pin assemblies have springs inside them, and they can launch the top part of the key pin assembly a loooooong way.

I can assure you that those top parts of the key pin assemblies can play a really, really, really good game of hide-and-seek.

Luckily, we have tile in most of our house, or never would have found it. As it was, it went from the living room, down the hall, and into the front of one of the bathrooms. I'd estimate it traveled 15 meters from where it launched. Found the spring about 2 meters from where it launched. I spent an hour pulling off couch cushions and moving furniture around before I worked my way down the hall with a flashlight held near the floor to highlight anything on the floor, but I did find the key pin part.
So I recommend that if you want to take apart the key pin assemblies from a U-Change, do it inside a small bag.
Gordon
Just when you finally think you have learned it all, that is when you learn that you don't know anything yet.