They’re actually supported it four spots - one screw, one bracket and a pair of fender stays. They don’t rattle but I removed the mudguards due to noise from them rubbing the tire over bumps. I’ve heard the Juiced Bike and Planet Bike fenders also make noise from the mudguards hitting the tire so I don’t think it’s a brand specific issue.Just one screw for the rear fender. Does it rattle much?
The rack just sits about 1/2” to the right of center towards the drive side when viewed from the back. So most disc-brake specific racks should work. Although I do think you want adjustable struts to get it to work on the newer CCS/CCX frames. The mount for the rack struts is placed higher up on the newer bikes.
You want 28/29/700C x 60mm fenders for the CCS2. The bike has 700C wheels (not 26”.) But yeah, Planet Bike Cascadia should work just fine too.