Right now, your guess is as good as mine. Landon didn't appear in the post-game press event, though he scored twice. He was hustled off to some pre-arranged appearance, so no reporters were able to ask him what he said to Pat Ianni.
There's a Landon quote in my espn.com piece because a Galaxy press official recorded a couple of statements on the game from Landon before he left.
So what is that best guess that people have on what he said? I'm curious as to who might figure it out. I'll ask Landon about it when I can.