Is it true that a man's prayer alone in his field upon hearing the call to prayer, if going to the mosque would take a long time and cause him to miss the congregational prayer, yields a greater reward than congregational prayer?

If someone is far from the mosque such that they cannot join the congregational prayer after hearing the call, then they are not obligated to attend it. If they pray alone due to an excuse, they incur no sin, and it is hoped that they will receive a multiplied reward for their sincere intention. However, we know of no evidence that their reward is greater than the reward of someone who actually attended the congregational prayer, because congregational prayer is twenty-seven times more virtuous than individual prayer. And the reward of one who performs an act of obedience is greater than one who was unable to perform it. The hadiths affirm that Allah bestows His grace upon whomever He wills.