Welcome to the community.
Because you seem to want your hub inside a Faraday cage, may I suggest that you do something similar to the Lewis Heidrick (@lewis.heidrick) External Antenna mod and, instead of mounting the antenna on the case of the hub, mount the antenna on the rack case, with coax between a connector on the hub case and the antenna. Be aware, though, that each connector in the RF path, and any significant coax length, can attenuate the RF signal.
Best, though, would be to use the standard External Antenna mod and put the hub on top of the rack cabinet or mount it to the wall using one of the 3D printed hub mounts that you can find in this forum.
