Aluminium or steel forks that don't have the mid fork built in threaded hole for bolts can safely have c clamps tightened onto them to hold the rack on mid fork. It's not a problem for the metal.
Carbon fibre however is very strong with taking forces in certain directions, but is not safe with something clamped around it like a c clamp as the fork could get crushed and broken when you tighten the clamp. This would then lead to a failure of the fork.
You hear it all the time in formula one cars where suspension pieces are made of cf, super strong to take forces in a certain direction that the piece is designed for, but if a mechanic leans on it, it can crack.
There are some cf forks with built in rack bolt holes, but quite rare. My bike has one, but specialised stopped using them after about 5 years and put on an aluminium fork to avoid any problems.
Read up on cf and how it can't have stuff clamped on it. You really don't want to mess around with compromising the integrity of a carbon fork.
Also don't forget that your bike and fork were not designed for touring, especially not the front end.
Thanks for the information. I'm looking at a lightweight trailer that I may purchase. Only issue I'm having is finding a spare tube for the trailer! The manufacture doesn't carry them oddly enough.