This question crops up quite regularly usually with regard to bank loans overdrafts which people have left behind when they return to the UK.
If the contract is in UAE, they will have to take her to court in UAE and get a judgement there and, once they have that judgement, they can then take enforcement proceedings in the UK. That would be to enforce the judgement, not decide the issue.
Whether they would go to the trouble of enforcing the judgements of the UK or not would be entirely up to them. If she has no money and no assets (house et cetera) might want to write back to them to say that she has no assets and that if they press for this money, he simply has not got it and he would have no alternative but to file for personal bankruptcy.
Faced with the cost of making someone bankrupt and actually getting no money out of it, many organisations like this will simply let it go. However it could resurrect in a few years time and hence it might be an idea to come to an arrangement with them, pay a much lesser sum (perhaps 10%) in full and final settlement.
This is of course assuming that there is something in the contract documentation which says that if the contract is broken, she would be liable for these costs.
Can I clarify anything else for you?
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