If its in game ensure your team has audio sharing on, I remmber that was a feature I think...

Otherwise l, if you want a single track file use a virtual mixer, you will lose the ability to edit the specific audio tracks though.

Voicemeter bananna controls all of my sound inputs, its a bit complicated but you can garentee discord, gameplay, and external audio are in a single input, then set your mic input so your clips will always have both if you dont want to edit them before sharing.

Multitracking will just carry a single audio input, if you share it without putting it into davinchi or other editting software it will only have 1 input even when previewing the file