You did not mention how much water was flowing out of the wort copper tubing. One would think water running through the hose would not necessarily build up enough pressure or force to allow much of it through a pin hole in the inner wort tubing. So, if there was a lot of water flowing out of the wort tubing, I would imagine somehow the inner tubing was crimped (possibly when you made the CFC) and eventually just failed (snapped). Perhaps when you moved the CFC. Or if the inner tubing was not all one length and you used a coupler, the soldering on the coupler failed.
Out of curiosity, I would try running water through the inner wort tubing to see if the flow of water coming out of the hose connections is the same. If the inner tubing has a leak, I would imagine the water flow would increase since there would be more water pressure trying to get out.
