Launch control should be:
1. Foot on the brake
2. Right foot all the way down past the click.
Way more easy than that confusing sport mode - DTC - M1 - praise God. And there should be a warning on the dash saying why it doesn't activate, like "engine not warm enough for LC" or "Can't use LC during break-in period".
That been said, that's a really quick time without LC given the conditions!