Astrology is a science based on some Mathematics as is Medical Science. When you are ill, you go to a doctor who treats you with his own diagnosis and many a times he goes wrong and you continue to be ill. And what do you do? You consult another doctor without any guarantee that he will cure you. Is it not? It is a matter of trust. Isn’t it?
There are many astrologers in Mauritius too. Perhaps you will be better advised to visit one of them. Astrologer Arya is quite famous. You try to visit him. And ask your question to him whether he can predict for certain whether your missing brother could be traced. And later if his prediction does not come true, you can ask for a full refund.
There is no guarantee for any of the astrological predictions as is there is no guarantee about God and the belief that He will always do you good. Astrologers or for that matter every scientist only evaluates a situation based on evaluations of observations and it need not necessarily come true. When a meteorologist predict rain in Mauritius and it does not rain, what do you do?!!!!