All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
The juristic scholars talk about a similar case in which a man swallows money belonging to him and then dies: is it permissible to split open his belly and extract it? The scholars give two different opinions about it.
The first is that his abdomen should not be split open. This is the prominent opinion of the Hanbali scholars of Fiqh and one among many opinions belonging to the Shaafi‘i juristic scholars.
In Al-Mughni, Ibn Qudaamah says: “Chapter: if someone before his death swallows money which may be his or belong to others. If it is his, his abdomen should not be split open because he has consumed it during his life.”
The other is to split open his abdomen and it is one of the opinions among the Shaafi‘i scholars of Fiqh and the prominent opinion of the Maaliki juristic scholars, upon the condition that the amount should be significant. Khaleel Ibn Is-haaq says: “And split open the abdomen of the deceased when the money he swallowed (before his death) is much.”
This is understood from the speech of Shaafi‘i scholars of Fiqh who give an example of swallowing a precious jewel. It is also understood from the speech of Ibn Qudaamah that he inclines to differentiate between what is valuable and what is of no value. He says, completing the previously mentioned phrase: “If it is little, he should be left alone and, if it is much and valuable, his abdomen should be split open and the money extracted because this is meant to safeguard wealth from being wasted and it benefits the heirs who are entitled to a part of this money due to his (fatal) illness.”
This opinion is most certainly closer to what is correct, Allaah Willing. Being so, there is no harm to extract the platinum screws from the deceased if they are really valuable.
The answer to the other aspect of the question seems clear from this, which is that it is due on that man to give back these screws to the family of the deceased if they were his property.
Allaah Knows best.