Is there any reprehensibility in not adhering to God's dispensations for daily travel, and what is better between fasting and observing the dispensation for travel, given that the workplace is 99 kilometers away and the questioner wishes to fast during the months of Rajab and Sha'ban?

There is no specific Sunnah (definition) for fasting the month of Rajab, and all the hadiths reported concerning it are fabricated. However, Rajab is one of the Sacred Months, during which the Prophet, peace and blessings be upon him, encouraged fasting. As for the month of Sha'ban, the Sunnah is to fast frequently during it, following the example of the Prophet, peace and blessings be upon him, who used to fast a great deal during it and say: "It is a month in which deeds are raised to the Lord of the worlds, and I love for my deeds to be raised while I am fasting."