Seeking where Robert Lindner actually served during WWII

With whom did psychologist Robert Lindner actually serve during World War II?  I have been conducting research relating to a case study written by Robert Lindner and published in his popularized book The Fifty-Minute Hour.

Lindner, who trained at Cornell and later under Theodor Reik, worked for a few years as psychologist at the federal prison in Lewisburg. But during World War II he enlisted. His obituaries (he died in the mid-1950s) state that he was a Lieutenant Junior Grade in the Uniformed Health Service, but to my surprise, that department claims to have no record of his having been in their ranks. So where did he serve? There is little to no doubt that he did; he was a well-known figure at the time.

Internal evidence in the cases and scattered reminiscences from the years after his death indicate that he had some sort of security clearance and had worked, during the war, in some sort of intelligence or counterintelligence capacity. I do not, however, find him named in the O.S.S. files. I wonder about the intelligence services of the army, navy, and state department (especially the latter). I also have reason to believe that he was stationed in the New York City area, quite possibly on Ellis Island (which was administered by the Uniformed Public Health Service and where many suspected Nazi sympathizers were interned - his job may have entailed evaluating them & trying to identify the actual Nazi agents in their midst). It seems likely that whatever agency he did work for managed to insert him into the Ellis Island staff in the guise of a Uniformed Public Health Service officer. But which agency? And where are his service records?