Is it permissible to subscribe to a program for investing money through an Islamic bank that allocates an amount of 100,0 to the participant's family in the event of his death?

Investing money with Islamic banks and institutions according to Sharia guidelines is permissible. However, allocating a specific sum upon subscription is ambiguous regarding its recipient (the bank or the investor?) and whether it is part of the capital or the profits, or if it is a subscription to a cooperative insurance fund given to the deceased's family. If the latter is the intention, then there is no objection. But if it is from the mudarabah (profit-sharing) capital or profit, then the transaction is not permissible, because mudarabah becomes invalid if the mudarib (entrepreneur) guarantees the capital or if a fixed profit is specified, turning it into an interest-bearing loan. The reason for the allocated sum, its recipient, and the nature of the transaction must be clarified to properly conceptualize the issue and rule upon it.