Without the requested information, I can only provide you with the following general response, which will hopefully still answer your query. First of all, I am sorry to hear about the issues you have experienced in your situation.
In terms of your legal options, you are now unfortunately too late to make a claim for unfair dismissal against the as that claim has a 3-month time limit and this was 2 years ago.
The withheld wages would have also been subject to that time limit, although there is an alternative where you can make a claim in the County Court under a breach of contract claim, which has a 6-year time limit.
The repercussions of this, such as the effect it had on your health, will be a personal injury matter and you have to show that your employer had breached your duty of care and in the process you suffered injuries, which can also include mental trauma.
As this can be a complex matter, the merits of which depend on he specific of the case, it is best if you approached a personal injury solicitor directly to discuss your claim and they can conduct a more detailed case analysis to determine if you have a case.
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Hopefully, I have answered your query in a way that is simple and easy to understand. If anything remains unclear, I will be more than happy to clarify it for you. In the meantime, thank you once again for using our services.