The pain in the arse was that my friend who has a degree was rejected by the same
centre. She must have been able to tell that I have innate teaching abilities.

More likely they found that you was easier to exploit, rip off and not likely to be able to quickly find better employment elsewhere. For a shit school, it's the best alternative available, when you can't find an employee that is truly loyal out of their own free will. A degree-less working class hero or whatever your last alias called it.