They know that not every school can offer identical programs of instruction. Not every school may be able to afford laboratories for teaching biology, chemistry, physics, geology and other sciences. These variations in experience are expected and welcome. Students should be exposed to different opportunities. And their different experiences and individual choices will naturally mean they develop different skills and knowledge.
Employers expect to see variety in students' experiences and in the totality of their skills.
For consistency, though, the Certificate of Mastery should only represent that portion of the student's work that illustrates mastery of the same skills and knowledge that any other student having a Certificate also has demonstrated. For the Certificate to be useful, it must be a common denominator. It must be instantly recognizable. That it includes basic work-related competencies. Many frustrated employers declare that if they could only find youth with strong academic skills, they would gladly train them in the specifics of the job.