The end of the wire has to be filed to a sharp taper so it wedges the detent to the side as it is inserted. I made a tool using a coat hanger bent into a "U" shape with the two ends filed to a point. I think the wires had to be about 4" long to straddle the key, but in your case there is no key so they can probably be shorter.

Once you insert the tool, you need to pull outward with the key to withdraw the cylinder. You might have a problem with that since the key is broken off.