Based on a few tweets, evidently Josh Gad was supposed to be in the LaChiusa number as well...
"Unknown fact of the night:I was supposed to perform on tonight's Tony's & couldn't because of scheduling. Hint: you'll know it when u see it"
"So bummed I couldn't be there tonight to join @AndrewRannells and
@meganhilty and the gang for the Tonys tonight. Scheduling conflict."
"You pile up enough tomorrows, and you'll find you are left with nothing but a lot of empty yesterdays. I don't know about you, but I'd like to make today worth remembering." --Harold Hill from The Music Man