It probably would have been fine if the cake on top wasn’t too dense or covered with fondant, which adds weight to it. The biggest risk would have been the cake sinking onto the bottom cake, but in all honesty, if that had happened to me I wouldn’t have slept a wink the rest of the night worrying about it. So, like you, I would have gotten up and added the support. Don’t feel bad, things like that happen to all of us at one time or another.
DJ - Fun Fiesta Cakes