Ribbles individual oddities aside, don't forget that front wheel clearance is due to the fork only, irrespective of the frame. Rear wheel clearance is due to the frame design and specifically the chain/seat stay lengths and brake bridge "height".
If those are Deda Black Rain carbon forks (I can't quite tell, but they look like it) then you won't get 28mm tyres in them with mudguards, not even with advanced Volio-esque zip-tie mudguard mounting techniques. 25mm+guards max.
Chainstay length looks ok, more than enough space between mudguard and seat tube for another 3mm of tyre. Can't tell about the clearance at the brake bridge from those photos but I'm guessing that's where the problem lies.