Hey, all things are possible with time, and money lol.
I don't know if you could retrofit the OEM equipment from a 2013, but a couple questions should point in the right direction. I don't have the ram box setup so my apologies if these questions seem trivial.
1) electric locks on the rambox?
2) electric locks on the tailgate?
If you already have those you could wire them directly to the existing door lock harness in the truck. I probably wouldn't even bother with a relay since the current draw should be pretty low. Just do one component to each door, or run one relayed hot-wire back, and split it to all three.
I would probably put a diode in there though just so if you hit the lock button in the rambox (assuming it has electric locks) it doesn't try to send any current running back up to the truck's ECU.
You could do the same thing for the unlock as well.