the factory instructions do not say anything about having to have one of the original remotes... not for these cars, anyway.....
The directions you quoted aren't in the manual. I'll give it a shot today with the one remaing remote. I believe it is in some way active, as a red light was flashing on the top center of the dashboard. I'll let you know the results if this works.
2016 Ford Fusion Energi Titanium - Still trying to figure out what I can do
2006 Mercury Mariner Hybrid - K&N Drop in filter. Not much else you can do...
TOTALED 9/2016 - 2004 Impala SS
SOLD 3/2013 - 2000 Grand Prix GT