Send them a 'Solicitors' letter.
An Arabian one if you can??
Don't contact them yourself, Use a company to represent you legally.
If you contact them yourself, They may suspect that you are not worth 'Paying' nor a threat and/Or may just laugh at you??
Push a good Solicitor onto them, That's what you pay them for and hope for the best.
I doubt VERY much that Etihad are short of a few pounds & pennies!!!
Good Luck Anyway.