I picked up a rollback/unwind 2016 Spark EV (875mi) a couple weeks ago, and it only came with 1 key :-/

The software for the WT-4 was called the WT-4 Setup Utility, but now that it supports the WT-5 and other devices the name has been changed to Wireless Transmitter Utility. Notices. This software is for users of WT-7, WT-6, WT-5, and WT-4 wireless transmitters, UT-1 wireless communications units, and cameras with built-in Wi-Fi and/or Ethernet. Here at FreeRemoteInstructions.com we are your source for free instructions on how to program your Toyota, chevy keyless entry remote control and all other kinds of vehicles, both foreign and domestic. Whether you drive a car, a truck, or an SUV we have the information you need to program your remote.

Having only a single key is a recipe for disaster, so I promptly ordered PN 94543206 (my original key is 94543205...) and had it cut at a locksmith yesterday.
Anyhow, the manual for 2016 doesn't seem to exist, nor did I receive one with the car, so I looked up the manual for the 2015 and there were procedures within. They do not seem to work.
What I did:
0. car not plugged in to power
1. approached car
2. unlock using remote
3. open flap on emergency key cover (ignition area)
4. insert existing key into ignition keyway
5. nearly immediately insert new key into driver side door keyway
6. turn door key from middle position to unlock position (counter-clockwise) 5 times at moderate speed (not trying to whip it from neutral to unlock quickly, though I did try at varying speeds) -- sometimes I tried more than 5 times, sometimes I tried faster, and sometimes slower

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7. wait for anything to show up on the DIC, only usual driver entry information is shown (charge status, plug in to charge, mi remaining, etc.)
8. DIC goes blank after a while (idle timeout), and I try to repeat this all again several times, to the same effect.
The DIC never says 'READY FOR REMOTE' etc. I cannot proceed beyond step 2 below.
I thought the 2016 was practically a newer 2015... Has the procedure really changed, or did I do something wrong?
Verbatim from the 2015 manual:
Programming with a Recognized Transmitter
A new transmitter can be programmed to the vehicle when there is one recognized transmitter. To program, the vehicle must be off and all of the transmitters, both currently recognized and new, must be with you.
1. Remove the rubber cap on the steering column. Press the button on the recognized transmitter to extend the key blade. Insert the key blade into the transmitter slot.
2. Insert the vehicle key of the new transmitter into the lock cylinder on the outside of the driver door and turn the key to the unlock position five times within 10 seconds.

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The Driver Information Center (DIC) displays READY FOR REMOTE #2, 3, 4 or 5.
3. Remove the recognized key and place the new transmitter into the transmitter slot.

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4. Press the POWER button. When the transmitter is learned, the DIC will show that it is ready to program the next transmitter.

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5. Remove the transmitter from the transmitter and press X (UNLOCK button)
To program additional transmitters, repeat Steps 3-5
When all additional transmitters are programmed, press and hold the POWER for 12 seconds to exit programming mode.
Replace the plastic trim piece from the small storage area.

Here at FreeRemoteInstructions.com we are your source for free instructions on how to program your Toyota, chevy keyless entry remote control and all other kinds of vehicles, both foreign and domestic. Whether you drive a car, a truck, or an SUV we have the information you need to program your remote. FreeRemoteInstructions.com offers detailed step-by-step directions from the manufacturer of your American or imported car or truck, detailing how to program the key fob remote control, or programmable key for your vehicle. If you have lost a key, replaced a defective key-less entry remote, or added a new key, we have the instructions that you need to make the remote control work for your car, truck, van, or sport utility vehicle. Please select your vehicle from the menu at left. We have assembled an alphabetized list from Acura to Volvo… Just click the selection to see what models and years are available for your application. Thanks for visiting!