Your reference to Hawaii was a help but I could not find much more than this but it is a start. The 19th Bomb Group at the time was operating out of a place called Singosari. Singosari is a small town in Malang, East Java, Indonesia, on the Java Island. For a couple entries I read, it sounds like the “Guinea Pig” came to the 19th BG out of Africa. Some of its missions were probably flown while there as well.
B-17 Flying Fortress Units of the Pacific War,By Martin W. Bowman
“During its long career GUINEA PIG flew more than 200 missions before finally being written off on 31 August 1944.”