Investor can work as Director in another country

Dear Members,
I will appreciate if anyone can help us. My uncle is having investor visa of Bahrain.He hired a manager here in Bahrain and this manager is looking after his business.Now he got very good opportunity in Dubai a Director job.Now can he work in Dubai as Director work permit as he still has Bahrain investor visa that he don't want to leave at all.Do u think this job will affect his investor visa according to Bahrain rules or Dubai rules or he has to buy some shares in Dubai to work in that Dubai company.
We want to follow law in any case.I appreciate your advice in this matter.
Thanks

I really don't think this matters at all .

Investor visa is given to someone who has his own Commercial Registration .
My cousin working in Saudi , has his Investor visa in Bahrain too .


This really shouldn't be a problem .