Why would someone sign contract written in language one does not understand?
This is quite common in the Middle East.
If you don't sign it then you don't get the job. It is as simple as that.
Their country, their language, their rules.
Why would there be any differences in English translation with reputable company?
How do you find a reputable company when you have never been to that country before?
I know of a number of people across various industries who have been stung by the "translation error" routine. Often, there is no western-style legal recourse and you have no option but to just 'suck it up'... again - their country, their language, their rules.
There are exceptions, but as a general rule: if you want all your ducks lined up in a neat row (and don't want anybody moving said ducks when your back is turned) then working in the Middle East is not your best choice.