All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
We did not understand what you stated in the second part of the question, so we cannot give you an appropriate answer to it.
Nonetheless, we will mention two following matters in brief:
Firstly, whoever dies and leaves behind one son only and does not leave any other heir, then the entire inheritance is for this son by Ta’seeb (having a paternal relation with the deceased and not having a specified allotted share). So the son gets, in this case, the entire inheritance.
Secondly, the will which states that the inheritance should be given to some heirs and excludes the others is not valid. This is an unjust will and it is of no consideration. The division of inheritance as prescribed by Allah is more deserving to be implemented.
Allah knows best.