Depending on what aspect of the Layers API you plan on using, but I assume you’re trying to use Camera Mode, you’ll have to call runRenderingContext with slight variations in the params. Here’s what it should pretty much look like if you plan on utilizing Camera Mode straight from the docs:
You cannot call Camera Mode for other participants in the meeting, only for yourself. Is that what you are trying to do? Do you have any screenshots of what your console says when trying to run drawWebview?