I would take Discovery University's claims regarding employability with a grain of salt. When they discuss employability, they include any type of employment post-graduation, even if it's unrelated to the degree. Most universities will provide some level of assistance but you need to take into account universities will have thousands of students with a small employment team.
It's really down to you to find employment and to develop the skills, through internships, placements etc.
I would take a look at, the average salary for business/management graduates as this tends to be a more accurate measure. From what I can see its around 25k before 5 years.