Every DC/DC converter type also has other harmonics and ripple, so what helped in your case might helps in the other, but not necessairly. I currently have my CNC mill running, so I could not hear in your video if you had the motor running (and every bec and motor also behaves differently) or not. To me it looked more like remaining ripple from your DC/DC converter as noise introduced by motors usually looks different (bigger stripes).
Makeing a good clean power train is sometimes not so trivial. As mentioned, the trouble also could be caused by other things, that's why I suggested to reduce the setup to the abolutely necesairy things, then do range tests without motor to see if we face an issue with the HF parts including the antennas cables etc. or if it's power source related. In situations like this you need to exclude causes to get to the bottom of the problem.