Is it obligatory to pay blood money (diyya) in cash to the family of the deceased, despite a financial compensation being paid to them by an insurance company, and what is the amount that must be paid?

This is involuntary manslaughter, which requires expiation and blood money (diyah). The expiation has been performed. As for the blood money, it is the responsibility of the 'Asabah (male agnatic relatives), and there is no harm in it being paid by the killer himself or through insurance.