MyHipsHurt
You can't ask for an MR until a Decision is made, there may be a short window for you to write to the DM before they do this, if you decide to do this then send it to the DWP office dealing with your claim, I would include a statement that your letter is not a request for an MR but you reserve the right to request one at a later date.
You should make a formal complaint to the Assessment Provider
Complaining to the PIP Assessment Providers You can also make a complaint to the Nurses and Midwifery Council.
Gordon