Expanding on what I posted before. Wiki say that the single tail PB4Y-2 was used tell late 1944. So the PB4Ys have to be twin tail PB4Y-1s (B-24s). Wiki also says that the ERCO nose ball turret wasn't fitted tell mid 1943 would would make since as that was the time that Army B-24s started being fited in large numbers with turrets in the nose.
This leads me to think that the PB4Y where just Naval colored B-24Ds for your mission.
EDIT: They where Navy B-24Ds. Pacific wrecks list one of the B-24s from the mission. It was build as a Army B-24D.
http://www.pacificwrecks.com/aircraft/pb4y-1/31948.html
Link for another from the same mission. Same story, build as a Army B-24D.
http://www.pacificwrecks.com/aircraft/pb4y-1/31970.html