Ajax Baumler resigned from the army to join the AVG but was refused a passport because of his service in Spain, so he didn't go to Burma with the rest. (That's why there were only 99 pilots instead of the intended 100.) He tried to get to Chennault as an army officer in December 1941 but was turned back by the Japanese attack on Wake. He set out a third time as a captain by way of Africa, and reached Chennault's headquarters in April or May 1942. See
www.warbirdforum.com/baumler.htm
He did fly at least two missions with the AVG and claimed one Japanese plane shot down. However, he was a uniformed officer of the USAAF at the time, not a member of the AVG.