Thomas Cook are an absolute nightmare when it comes to dealing with complaints, or giving a just amount for compensation. I wrote about my nightmare tour with TC entitled 'Thinking of going on Rio and Iguacu tour with Thomas Cook'? Thomas Cook tell you it would take 28 days in the hopes you will give up and forget about it. Basically they try to fob you off.
My holiday took place in July. I filled out a complaint form in Brazil and since my return have written 3 letters to them. After my first letter, they sent one letter to say they needed 28 days. After the 28 days was up I phoned Thomas Cook and they said..Oh we are really sorry did you not receive our letter stating we need a further 28 days to investigate. He then said he would send another letter, which I received 2 days after the phone call. Four days later I received the letter I should have received in the first place.
I was not happy with the result when they did finally write to me. They assumed we received our compensation..which is ridiculous as if we did receive it, we would not be writing letters demanding more compensation.
Following this, I wrote a very strong letter to put them straight. 2 weeks later they wrote to me saying that they are dealing with my clients complaint and that they will get back to my client. They thought I was a travel agent writing on behalf of a customer. And this is A Customer Executive writing.

They haven't got a clue.
So I would suggest to keep writing to them. Don't give up as that is exactly what they want you to do.
Good luck