I am making my cousins wedding cake in a few weeks and I am wondering what is best to use to pipe scrolls on the fondant, royal icing or buttercream. I have to travel with the cake about 1.5 hrs. I'm scared if I use royal, the decorations might crack, but if I use buttercream, I'm scared that it will get kind of soggy on the fondant if that makes any sense. Any advise would be very appreciated!

If the scrolls are being piped flat onto fondant, I would use Royal Icing.

the scrolls will be on the sides of the cake

I would use royal icing if I were u. Its not gonna crack as long as you don't touch it.

Ok royal icing it is! Thanks for responding