This just means that the call fell through the script and hitting the end with out being treated.
I assume you have tried monitoring the script from Script Editor to see which script node is failing.
Which node is it bailing on? Does the same call flow work when you try the call tracer tool?
The Router process in the Router node may have more details as to why the call is bailing out if its due to configuration errors. Use the dumplog tool to dump the router trace file. At the point where you need to start looking at logs is probably the right time to open a case with your support team.