These clips are wild and literally out of this world! Funny that a shout of "Tango Delta" precedes "touchdown confirmed". Both indicate a TD, but I'm not sure why the former needs to use the phonetic code. I also thought the quality was much better when I set it to 1080p, the browser default must be much lower. It gets grainy right during touchdown, but I haven't heard if a higher quality version is coming or not.
The "TD" call is wheels down on Mars. However, at that point the sky crane is still tethered to the rover. If the tether separation isn't successful, and/or the descent stage impacts the rover, then you can't say "We're safe on Mars."
Note that this edited video is compressed with the timeframe. The gap between the "TD" and "safe on Mars" callouts were longer as it happened.
So apparently there's a secret code in the pattern of the parachute.