"I can sing "Nobody Can Save Me" and "Battle Symphony" from the new Linkin Park record, and I can sing them because I wrote them, it was me and my friend Jon Green. And I sang the demos and they're written in a way that I can sing those pretty well. But lyrically, a little too hard. I just feel like I know that in the long run, if I put that in the set, it's only going to be a show or two before I go, "I don't want to sing that. I don't want to sing those words."
Of course nobody knows for sure, but it's possible that Mike just didn't want to make a pun based off of Battle Symphony's title because of how much that song means to him personally.
Then again I could be reaching and the answer could be that he literally just forgot about that suggestion altogether lol