Info on sync audio on "waveform and append"

Hello guys,
I'm having some troubles working with a new kind of video.

So, I have a bunch of clips recorded with different cameras and 4 audio tracks from external mics for 4 different people.
I tried everything and in the end the fastest way was to sync mics audio with the main camera videos "based on waveform and append".

The problem is that now the audio clips seem to be trimmed and locked withing that main video clips range (I see a white dot on those audio clips) and I can't fill the gaps occurring from the insertion of clips from other cameras that have different leghts.



I attach an image. The video above is a second camera, the orange audio was added manually, and if you look at the next clip, The starting line is red and I can't extend the audio even if it exists in the original file.

Is there a way to do that?

Thank you!

Syncing the audio will restrict it to the video duration. Just how it works.

I see...well I think the turnaround could be a manual sync on a new track to recover the lost gaps, and then get rid of the previuos locked audio.

What is the best option in your opinion to sync more than 1 video source with more than 1 mic source anyway?

Do both video and audio have timecode?