Is it permissible to use a car owned and maintained by the company for official and personal use if it is highly probable that the company leased it from a usurious bank, knowing that the user is not a party to this transaction?

If the company leases the car from an interest-based bank through a lease-to-own agreement, then it is not permissible for you to use it for two reasons: First, the car is acquired through a corrupt contract, so the company does not own it, and its disposal of it is not valid according to most scholars. Second, using it constitutes an endorsement of an evil and a neglect of its denunciation. However, if the lease is an ordinary one without ownership transfer, then there is no harm in using it, because the funds of an interest-based bank are mixed with lawful and unlawful elements, and dealing with someone whose wealth is like that is not forbidden.