Is it permissible for the private company of a manager, who works for a German company in Qatar and is responsible for referring bids to local companies and purchasing complementary equipment, to be one of these local companies that deal with the German company, knowing that he can offer a lower price and better quality?

The questioner is a trusted private employee, and he has the status of an agent. An agent is not entitled to act except in what is in the best interest of his principal, and he does not deviate from what he has been authorized to do. Among the rulings of agency is that it is not permissible for an agent to deal with himself, whether by selling, buying, or leasing, except with the permission of his principal, according to the more preponderant opinion. Therefore, it is necessary to inform the management of the German company that you are the owner of the private company with which the transaction will be made. Otherwise, you are not permitted to transfer the bids to your private company.