The key word here is "solution." If your code is supposed to do a job, and for whatever reason it's not doing that job, then you do not have a solution.

Code that doesn't do the job is worthless, no matter how testable and well-designed it is.

Of course you can debate whether this is a management (scheduling, resource, PM) problem or a developer (competence, architecture, tool choice) problem - most likely some of both.

But whoever is responsible, it's still a non-solution.