Generally a company would compensate an employee for actual costs that he has incurred to give effect to his duties. Based on this, in principle it would not be acceptable to claim the taxi fare when one has in reality incurred the cost of travelling by bus. However, if one negotiates this transparently with the company, or claiming the taxi fare is clearly allowed by the company even if one has not travelled by taxi, as a matter of company policy, then one could claim the taxi fare, even if one has travelled by bus.
NB: Such company policy should be clear and unambiguous and claiming such amount should not entail the slightest bit of deception or misrepresentation.
And Allah Ta’ala Knows Best