The OSS was quite active in the Pacific - among other things, they worked with this guy named Ho Chi Min. You might have heard of him.
Remember, the US put its ethnic Japanese in internment camps. The Nisei units were all sent to the ETO so they wouldn't have a chance to defect (probably just as well for them - I doubt any of them would have survived Japanese POW camps had they been captured, and the potential for friendly fire...). The US DID NOT TRUST its ethnic Japanese.
Note I'm not saying they were right (IMO they were quite wrong - the Nisei units in particular demonstrated that), but that was an overwhelming cultural bias at the time.
So, we've established that it is approaching ASB territory for them to have been sent. Let's flap some leathery gray-green wings and say they were. What would their target be?
Sabotage? Of... what? Japanese industry was so distributed that machine tools were often found in
individual houses. True, there were only a handful of major shipyards... and by 1943 they were chasing their own tails so hard that almost none of the hulls they put in the water contributed ANYTHING useful to the war effort. Aircraft? The Japanese produced so many that by the middle of the war pilots were being sent to the front with less than a hundred hours of flight time - often MUCH less. Destroying a handful of aircraft might IMPROVE the quality of the IJA and IJN aerial forces!
HUMINT? The US has usually been weak on that true... but it was getting so much valuable SIGINT that it is hard to see a few shallowly placed agents generating much useful info. Remember these guys aren't going to be Tojo's secretary, or one of Yamamoto's code clerks. Such a job requires too much background. Maybe someone planted in early 1942 could be well placed by late 1944... by which time what does the US need HUMINT for? The Japanese are on the ropes and their intentions are mostly irrelevant.