PIP without an official diagnosis

So I'm looking at applying for PIP, which I have been eligible for in the past on account of my ADHD, but because I started medication it was removed.
One thing in particular at my tribunal was the mention that some of my symptoms did not sound like ADHD but dyspraxia instead and because my PIP application was based on ADHD and not dyspraxia, i could not be awarded any points. The tribunal took place during covid via the phone which meant I couldn't express pyself properly

Since then I have been doing further research into dyspraxia and it does seem like I may have it as I display symptoms such as s a complete lack of coordination and balance, am very clumsy and constantly getting hurt, am hyper sensitive to touch, taste and smell.

I have tried to get a diagnosis through my GP only to be told that it is not offered for adults through NHS.
I also cannot get a diagnosis through Access to work as I am a civil servant and this was removed for civil servants earlier this year.

Does anyone know if it is possible to apply for PIP without an actual diagnosis?
If it's not possible to apply for PIP without an official diagnosis I'm going to have try to find close to £1000 for a private assessment which I'm hoping to try to avoid