I appreciate everyone's time and input but I'm getting very confused!
Perhaps this project is beyond my skill and knowledge level, but I was hoping someone could basically spell out what components I would need and a schematic (which I can just about read) of how to put them together.
I was hoping also to gain some knowledge and understanding through the process.
I totally appreciate and understand that this might not be the place for such basics though, so if that is the case, I really don't expect anyone to offer more time than they already have, and again say thanks for the input so far.
If this isn't too big of an ask, I've hopefully left all the relevant detail in my first post.
If you don't mind helping someone who literally knows almost nothing about electronics complete (what seems to a layman to be) a small project, I'd be immensely grateful for your input! If there are more details required than is in my first post, please let me know and I will provide.
EDIT: in rereading my first post I realise I may have missed a crucial point. The mic feed will go directly to the phone. What I would like to do is replace my janky splitter cable with a mixer to merge the audio from the phone (team Comms) and the Quest (game audio) to land in the same set of headphones.
Sorry if that wasn't clear before.