Is it permissible for an employee to receive a commission from tenants in exchange for an amount that the company refused to disburse to him, with the possibility of returning it to the company later?

It is not permissible for an employee to take a commission for their agreed-upon work unless authorized by the employer. The fact that the company delayed in paying the annual commission does not make it permissible to take the money without their permission, because the establishment and entitlement of the commission are subject to consideration. If it is established and not paid, the employee can claim it legally.