The linked item wouldn't work, because I need 1-female to 2-male Lightning, and that is 2-female to 1-male.

However...TRRS Y-cable might work. Something like this?

Any idea how much the extra connection would affect the signal? I'm hoping for pro-level audio to my iPhone.

And I would need an extra extension connection to go to my iPad. That wouldn't need to be pro-level, but it should still be pretty good so that the teleprompter will function optimally.

Thanks.