With Red footage, you are limited by the Red decode speeds, typically Red Rocket which does about 22-23 fps for Epic 5K. So not matter how many GPUs you use or how fast your CPUs are, you are limited the source codec.
Other formats like ProRes/DNxHD/CinemaDNG/ARRIRAW, etc. can go a lot faster as they are not limited by the source codec.
So if you need faster Red speeds, you can consider multiple Red Rocket cards!