I know this isn't using the mainline kernel, but is it possibly shinyquagsire23's joycon rail patch could be useful here? I don't know much about the L4T kernel so forgive my ignorance.
I'm not entirely sure this suggestion would work, but here is how you could possibly rig something together for In-Home streaming. There's a snap package called Anbox. Snap packages are meant to be universally compatible with pretty much all Linux configurations, and Anbox is built on that...