You say you used a customized template, but the error message says the question is of type sql_woodmont. That's not an out-of-the-box question type, so it seems you have created a new question type, rather than just customizing a template. In other words, you have defined a new question prototype at some stage, via the Advanced Customisation section. Was this deliberate? Note that prototypes cannot be run as actual questions - this used to be supported, but not any longer.
The error message says that the question you are trying to run is defined to be of type sql_woodmont, which means there needs to be exactly one instance of a prototype for that question type anywhere in the question bank for the course (except the quiz-specific bit, which is isolated) or any outer question banks (e.g. the system). The error message unfortunately doesn't tell you whether you have zero, or more than one, such prototypes. [This is fixed in the current development branch of CodeRunner.]
If you try to create a new CodeRunner question in the same category of the question bank as the question giving an error, do you see sql_woodmont as an available type? If so, you probably have multiple prototypes, if not you probably have zero prototypes. [This is not totally guaranteed, but I think that's the case for all recent CodeRunner versions.]
Since you say "Somebody else copied the question into a quiz", I'm guessing someone managed to copy the prototype as well. [There are checks in the code to catch attempts to create multiple copies of a prototype but some ways of copying questions bypass the CodeRunner codebase altogether.]
If you have multiple prototypes, then simply deleting one of them should solve the problem.
Another tool that might be useful to you is a script at <moodlehome>/question/type/coderunner/prototypeusageindex.php which lists all the questions in a course according to their prototype. I'm not sure, though, what it does when there are multiple copies of a prototype. But it might pick up an error - I don't remember, having written it over 10 years ago and rarely used it.