Employment Law - Grievance Appeal Letter

I am looking for a lawyer experienced and well versed in Employment Law, who can advise me on a case (Employee Vs Employer).

Status of case in brief:-

Employee feels subjected to following at work by line manager and company director:-

1. Discrimination (protected characteristic Disability).
2. Neglect and Lack of Duty of Care.
3. Bullying and harassment.
4. Pulled unfairly by manager for performance issues, without relevant or appropriate evidenced justifications. It is strongly felt and argued that the employer has not supported employees return to working in the office (proactively), and instead begun citing performance issues as a means to try apply pressure on employee.
5. The employer then went on to Cite for capability concerns when employee cited work stress and not receiving adequate and appropriate support from the employer.
The capability was raised by employer after employee returned from 1 month signed off sick (by GP). The employee feels the employer is pushing an agenda to dismiss using grounds as performance and capability, and not withstanding any acceptance of duty of care to ensure the employee was and has been adequately supported to do the job role, given the protected characteristics of (disability).

The lack of support has led to employee being impacted by stress and exacerbated medical conditions, which has impacted the ability for the employee to do their job in a supported and effective way.

Case
1. Employee tried to get a resolve informally (supported by union). This failed as employer was insistent a grievance must be raised in the first instance.
2. Employee Felt pressured to raise a grievance case, as this isn’t the route They wanted to take, as such, formal routes are extremely stressful, impactful and can create hostile relationships at work.
The director (employer) was insistent this be the route, and therefore Employee felt there was no other alternative choice (the grievance was then raised).
3. It is felt the outcome letter of the grievance investigation is biased and dismissive; and centres it’s focus on employee being the place of problems, and not holding accountability of how senior management have handled (lack of) the welfare and employment matters.
4. Currently In the process to write an appeal to the grievance outcome letter.

Employee doesn’t feel safe with employer and feels the work relationship has soured beyond relief.

Looking for a professional who can take on the case and produce a compelling appeal letter against the grievance outcome letter.

The view will also be to engage the employer towards a settlement.
Two Protected conversation letters have been exchanged by the employer in earlier dates (prior to grievance investigations), but turned down as was not agreeable.