The final setup will probably use the insulated tubing to connect the S5 to the vent and see if that makes it quieter as well.
My 3D printed ducts should arrive today, so I spent last night whipping up an insulated vent tube for the S5. I used standard 4" dryer ducting and some sticky foil-backed duct insulation. Adding this vent tube dropped the temp on the miner 1-2*C, I'm guessing the hot air wasn't getting out of the way fast enough without the tube and the hot air was backing up a little in the previous configuration.