Matilda, I've had two fits resulting from hypos in my working career, and just carried on working. This was in an office job in the civil service, and they could no more sack me than fly because of the disability at work legislation. That legislation, incidentally, does include diabetes as a disability. However, working as a waitress, the health and safety rules trump that legislation.
Having two fits due to hypoglycaemia would no more get you PIP than diabetes alone. I know one epileptic person who had a full career, and has just retired.
Having a single daytime fit will cause you to lose your driving licence for a year, if reported to the DVLA. If you don't report it, you are driving illegally.
And Owen, if you lose your driving licence for any reason, you can't claim PIP mobility however difficult it is to work or do the shopping just because you don't have a car or live out in the country. It's not a consideration that comes into the assessment for mobility.
Finally, you will never get PIP unless you can demonstrate that you need help dressing, preparing food, taking your medicine, mixing with other people and difficulty in communication. As you are working as a waitress, you simply won't qualify for PIP, because by the lights of the current government you don't remotely qualify. In any event, taking a job because your DLA stopped fatally undermines the claim for PIP.
Your ambition should be living a productive life with well controlled diabetes, not directing your energies to claiming PIP. That may sound harsh, but it's not meant to be. But that does drive the thinking of the DVLA.