I installed mine.
Did it a little different.
I took out the removable cargo area floor so that it would sit about an inch to an inch and half lower. I took the evse bag hook off the floor and drilled through the cargo holder, reinstalled the hook inside the cargo holder with some spacers under the cargo holder and longer bolts to hold it down to cars floor so it doesn't bounce around with the rough roads here.
Now I have a place to put spare tire changing accessories, evse adaptor cords, my away 16 amp evse, extension cords, little space heater, extra ammo, ect.
I may take it back out and weld in some D ring bases to the rear floor and attach a ratchet strap to these D rings to hold down the spare tire.
The away evse will probably end up going on the floor in the back seat since I use it between 1 and 4 times a week, but rarely use adaptors or extension cord with my evse.
These probably should have been a standard option or standard part of the design at least for on board charger hump cars.