Hmm, lets think about this........young Dubya, as the son of a Congressman, knows that the ANG, as an air defence (of USA) component of the USAAF, will not be called to Vietnam. He applies for a place and just makes the grade. He then spends all of his flying as a trainee only and, along the way, misses a medical check is therefore grounded systematically. He also knows that he is allowed to miss many weekends to sort out his other career interests. As one of many young pilots on the roll, his boss wouldn't know him from Adam and so far only one other individual has come forward to say he remembers him.
The guy was war dodging in a big way. AWOL? Hmm, difficult to categorise an absent part-timer as AWOL at the best of times. Did he receive pay for weekends that he didn't attend? Doubtful, if pay was on an attendance basis, because attendance records would be used (and he would be silly to get a mate to sign him in when he wasn't there). However if pay was awarded on a contractual basis, ie the assumption is that he will attend the designated weekends and for simplicity he will be paid regular amounts throughout the period of Service, then there is a possibility of some gardening leave. And, due to the glut of full timers getting the few hours available, there would be a lot of young part-timers doing a lot of gardening (not digging trenches, though).