Not going to lie, it is a definite workaround for not having a fully synchronized, timecode, EDL, auto conform, process ! But where I work, that is what it is !! haha And it does work.
In my case I usually only have 4 individual tracks to sync with a stereo mix , so less than you, but still enough to frighten a video editor.
However it again makes me wonder if Nuendo shouldn’t be able to sync similar audio events into groups, based just on the audio ( like NLE’s do ). The we could at least use a stereo temp mix event to be the reference to align other audio to. Maybe it is only an edge case.
There’s a thread about it here with some useful third party products which might help you.