Is it permissible to work in the maintenance of fire alarm systems and devices, and the installation of cameras and security systems for an insurance company and a bank, despite a previous fatwa that allowed this in a similar situation?

It is not permissible to work in interest-based banks or commercial insurance companies, nor in maintaining their devices, installing cameras, and the like; due to the impermissibility of Riba (usury/interest) and Maysir (definition) (gambling), and the impermissibility of assisting in them. As for repairing cars that the insurance company repairs, this is not repairing the company's car, but rather the cars of the insurance company's clients, and the assistance here is neither direct nor proximate.