Although a world record, why not placed in Guinness Book?

There is no such category in Guinness Book and this is the answer given by Guinness Book administrators:

"This is not something we can accept as a new record as each country has its own education system and within each country, each academic institution has its own methods for awarding qualifications. This also applies to professional qualifications as each governing body has different criteria on which their awards are based.

In addition we no longer monitor nation-specific records and therefore records that relate to a particular country’s education system.

With this in mind, there can be no fair and justifiable standard upon which to base a world record.

Examples of proposals we would not accept:
Most law degrees
Most Masters degrees
Most A-levels at A* grade
Youngest person to pass their High School Diploma

We do accept:
Oldest graduate
Most graduates in a single family"