john a bristow oss shanghai china world war two activities. how was he involved with oss ?

My grandfather John a bristow was a diplomat with us state dept and after a few years was employed by socony oil as an executive. he was friendly with mr. t.v. soong brother of madame chiang. after he came home from his brief cativity in manila aboard the gripsholm I have been told he was hired by oss to greet and meet with those arriving in united states from china for oss. can anyone enlighten me as to the veracity of this data ??