I am publishing your post and I hope someone might be able to tell you about their experience.
Be aware that the DWP are not so interested in the condition per se - but how that condition impacts your daily living and/ or your mobility. So it is quite possible for two people to have the same condition, and one person gets awarded PIP, and another doesn't.
I would also say - do not assume that the person reading your form will be familiar or even understand your condition so you need to make it very clear, the symptoms and the impact as per the specific PIP criteria.
The Guide to PIP claims and Reviews has sample answers for all the questions on the PIP form.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems