Watched other video starts - no issues.

Even with a short burst of prime fuel: -mix open, throttle cracked open: start cranking, the cylinders instantly are flowed with fuel.
I have to start with mix fully closed, and open when fired up. None of video start up need to do this.
And none of other BS aircraft have this problem
. I am very careful to lean all the time. Even TO and landing I have some lean. Shutdown I always run at 1500 rpm, and slowly lean to cutoff for a good plug clean.
.
Not sure how to read tablet. Fuel line left from venturi , is it prime fuel? I cannot find the mixture valve either. Would help for troubleshooting to find location of it.

. - BTW saving is a mess, but I guess you know it.

Thanks for plane! Hard to imagine it did ground the Bonanza.