Employment dispute assistance

I started working with a developer's hotels & resorts on Aug 17, 2015, as Director of Digital. They hired another Digital Director in early April. I was terminated July 28th. I have refused to sign the letter as I was going to Ireland that afternoon. I contacted them 2 days after and I advised that I would sign the letter based on the following:

* Full payment of 30 days notice & holidays owed.

* Full payment of yearly bonus, which, unfortunately, I had to learn after the payment of bonus to other staff members management did not approve. No reason was given for this.

* Payment of value of flight home per year of completion of 1 year.

* Payment for flight changes in December 2015 as per management request - AED 4K.

* Gratuity payment as per UAE employment law.No response has been forthcoming.

Am I better to go legal and just deal with them directly through a legal team? Should I go to Ministry of Labour?

Any advice on a good employment law specialist would be most grateful.