Please allow me to geek out a bit: A typical alternator is a purely electric generator which receives mechanical torque from the engine through the serpentine belt and replenishes the 12V battery. The mechanical heart of the e-torque setup is a glorified "alternator" which is a single device that allows bidirectional energy flow; Feed it current (from the 48V battery) and it will produce motion, or forcefully rotate it (by the engine) and it will produce current. An old and basic electrodynamic technology, really.
During a restart, the 48V battery feeds current to the "alternator", which produces torque, which gets sent through the serpentine belt, which rotates the crank shaft and starts the engine. Hence my allusion to push-starting.
Here is an illuminating quote from
How RAM eTorque Works | Green Car Journal
"Alternators only draw modest power from an engine’s accessory drive. However, eTorque’s motor-generators use their accessory drive belt to slow and accelerate these trucks, so the belt must be larger and stronger, and also must wrap farther around the pulley. It also requires a tensioner on both sides to keep belts tight as the motor/generator transitions from generating to motoring. The eTorque Hemi gets a larger crankshaft pully as well that improves the motor/generator’s leverage."
Edit: Regarding whether there's a traditional starter or not; here is a quote from a Zeigler article:
"Because of its greater efficiency in extreme temperatures, both the V6 engine and V8 engine with Ram eTorque technology will keep a traditional 12-volt starter motor, which is ideal for cold starts and the initial start of the day."