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The high coil secondary kV demand with no spark plug burn time can be caused by an open in the spark plug wire, which creates the high coil kV demand, then the coil doesn't have the kV necessary to arc across the spark plug's air gap, to the plug's ground terminal.

Remove a good spark plug wire that is not misfiring and use an ohm meter to measure the resistance of the plug wire. Then compare with the resistance of the plug wire of the misfiring cylinder.

Or a high resistance caused by an air gap or corrosion where the plug wire terminal connects into the coil secondary post.

The most common issue that I've seen over the years is an air gap between new spark plug wire's terminal to the spark plug's terminal, because the inside of the spark plug boot was not lubricated.

Remove the scope leads from the spark plug wires. With the engine running, spray soapy water on the coils and on the spark plug wires, then look for spark arcing to ground. Take a grounded regular test light, hold the tip of the test light 1/2" away from the wet coils and plug wires and look for spark

Look for carbon tracks on the spark plug insulator and in the spark plug wire's boot.

Looks like a secondary scope cable issue. I know in Pico 6, you need to click on the Colored Lead option when using the Colored leads to get accurate secondary waveforms.

If you can scope your Mercedes coil primary volts, you will see the actual spark plug burn time waveform.

This capture shows the primary coil winding volts and the secondary spark plug burn times, along with the primary winding current draw