I could be utterly wrong on this given my general ignorance of this battle (I've read articles on it and know it was a close-run thing, but nothing deep and exhaustive), but we're talking 1944 here. If the Japanese had won there, it might have made things a bit more difficult, but would it really have made much of a difference, considering Japan was just about to feel the wrath of B-29s from the Marianas Islands, captured in July/August '44? And was about to lose what precious little they had in the Battle of the Philippine Sea (though that was nearly an Allied disaster, for sure).
I'm interested in learning more as to what the consequences would have been. India would have suffered but could Japan really have invaded the entire subcontinent that late in the war - and maintained their holdings?