If you want to argue that you cannot use a wheelchair as it will make your condition worse then you will need medical evidence to support this, even though there is a doctor on the panel they will not come to this conclusion unless those treating you have specifically stated it.
Regulations 29 and 35 are explained in the ESA Claim guides, there needs to be a "substantial risk", without a documented history of falls resulting in injury I think you will struggle to show this.
Being restricted to the ground floor due to Health and Safety is covered by Reg. 29 under "reasonable adjustments in the workplace" so there is mileage in arguing this.
Speak to your GP about your using a wheelchair.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems
