Can certainly speed up some peoples workflow drastically, but hell, Red Giants wants 300 bucks for a Sync Tool. Thats insane. I dont get it why Vegas is not able to do it itself out of the box, even Final Cut has this feature build in...
If you (meaning, anyone) can hear beats, you can just line up your cameras footage sync'd to audio, (as you've done), employ 'Multicamera' function (as you've done) -
THEN, let the video play in real time and just tap the "s" key (split) - or the whatever asigned key for "add marker" first if you'd like -- on the beats; you can then go back and clean them a bit if necessary.
You can also reconfirm visually what you hear by looking at the audio wave forms, usually pretty obvious the strong beats. If you can't hear beats, you probably have no business cutting a music vid in the first place.
AS you point out, you will group individual beats, mostly in groups of four, or perhaps two, as you are suggesting in this song. That is for the per usual dance music, not talking about more exotic beat patterns.
(Automatic beat detection does work, but not always nor always perfectly, in my experience).
An extra hint if you want random camera switches with a variable length (for example a length of 1, 2 or 3 beats): in Vegasaur use "Switch Takes - Random" instead of "Switch Takes - Multicam". I saw another user (Adrian Vida) use this option and maybe someone else finds this option useful.
I've gotten away from syncing camera video to camera audio in my multi-cam. Found it to be particularly inaccurate with cameras placed at varying distances from the sound source. Getting better results filming a cell phone displaying time of day with seconds. A digital clap-board with milliseconds would be better but they're expensive and syncing on just the cell-phone seconds as they transition works pretty well for me at 30p. I've been using 2 synced cellphones back to back, held together by a rubber-band, to sync footage from rear- and front-facing cameras. Film them at the beginning and ends of lengthy segments and have never seen drift in any of the video. Except for cameras that drop frames between splits or media cut-overs.
Another approach is using lights for syncing cameras. I first noticed how inaccurate audio was when I shot a multi-cam rock concert under digitally controlled multi-color stage lights. It was pretty obvious when I stepped through the footage a frame at a time and watched the stage change colors on a different frame in each camera. I'm thinking of trying that out with a hue-light at house concerts.