All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
First of all, we ask Allaah to reward you for your adherance to eating from lawful money and we ask Him to make us and you steadfast on the truth.
As regards working in this restaurant, if the owner seeks lawful provisions, and personally makes sure that the company slaughters according to Islamic rites, then there is no harm for you to work for him.
But if he does not himself make sure about that, then it is more appropriate for you to seek other employment which is not doubtful.
In that country they usually use methods of slaughtering that are not accepted by the Sharee'ah, like electrocution, and the like. You have to know that whoever abandons something for the sake of Allaah, Allaah will recompense him with something better.
Lastly, we remind you that you should advise this man that he has to make sure himself about the credibility of this company that supplies him, whether or not it slaughters in a way accepted by the Sharee'ah.
Allaah Knows best.