I bought a cheap mini USB female to USB female adapter on Amazon for testing. I disconnected my inner USB hub (the one that wasn't working) and used the adapter to connect a USB flash drive directly to the Output of the front hub. It worked.
https://www.amazon.com/gp/product/B00474R7HO/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
(This part wouldn't be used in the final setup, it was just used to verify that connecting a flash drive directly to the Output on the back of the Front console USB hub worked).
So both hubs are connected directly to the HMI. I verified this worked a few weeks ago, but it means the Glove Box port has nowhere to connect to, however with this testing I should be able to connect the Glove Box to the front Hub and have everything working. There isn't a specific part that I can see that would do this, but they're just Mini USB connectors so a generic cable should work, would just need electrical tape or something to keep the connections secure.
This means I should be able to run:
HMI -> Front Console Hub (Green to Grey cable)
HMI -> Inner Console Hub (Black to Brown cable)
Front Console Hub -> Glove Compartment Port (generic Mini USB extension cable) https://www.amazon.com/gp/product/B015HKPDAE?pf_rd_p=d1f45e03-8b73-4c9a-9beb-4819111bef9a&pf_rd_r=HJVW9D9NJGNQETAPW9T4