Redundancy payment and Taxation

Can I please be signposted to the relevant section of guidance please? It's concerning a Redundancy Payout and it's Taxation. Redundancies are tax free for up to £30k. However the help I need is for one in excess of £30k. The member of staff was made redundant after her position was disestablished. She was supported in her post at work through her disability. However she could not be offered a similar role that was suitable for her physical limitations. We believe that their is a section of current regulations that would mean that as she was made redundant due to a suitable position not being available for her to move into due to her disability, then the whole of the redundancy payment becomes tax-free? Thank you very much for reading. Regards 

Name removed admin . 

Hi,
Information on Termination payments can be found per the following link:
Termination payments and benefits: contents
If you are unable to find the answer there, please contact the Employer Helpline on 0300 200 3200.
Thank you.