I think what OP is trying to do is find a cheap way to avoid the US estate tax while investing into US stocks. I guess RAK companies are cheap to set up and don't require and audit? So I could see how that would make sense (if you don't know how terrible it is to deal with UAE service providers and free zones).
But then you of course want to lower the WHT on dividends if possible, so he's asking if he can give IBKR his personal tax residency instead.
Like some guy here suggested in another thread (he didn't understand that this was illegal if the company doesn't actually pay the tax in his residency country).
If you only invest into US stocks, there shouldn't be ECI, so it doesn't matter if it's an individual or a company that owns the offshore entity.
But I also doubt it's a good idea to use a RAK company for this.