Representation:-

the fact that an employer was responsible for an employee's incapacity does not mean that subsequent dismissal because of that incapacity must be unfair - if that were the law it would mean employers would be obliged to retain on their books indefinitely employees who were incapable of any useful work.

For relevant general notes see Unfair dismissal/fair or unfair? or Unfair dismissal/capability and qualifications as reason for dismissal and/or Illness, sickness and accidents/dismissal/general .