I've worked on a lot of bows with broken strings (without string loops) where the string was damaged under the serving. Most had no problems but, a thorough inspedtion is called for.

Let's not be too hard on the tech, though. Most of us have had this kind of accident (learning experience) happen. "Man, it's 3:00 and I need to get to my stand by 4:00. Can you fix this?" "I think so, just give me a minute." THWANG!! "Man, don't try that again." That's where all those precautionary statements like "cut away from the string", "don't get the flame too close when you're melting the serving/string loop", and "don't bump the string/cables with your broadhead", came from.