Have you tried using the RX-A1020 zone2 RCA output connected to the Avantree Oasis Plus and use ARC from the TV to the receiver?
Edit: Perhaps I should read your first post more carefully
. The Avantree Oasis Plus, according to homepage, supports analog input and that should work if you connect directly from TV to the Oasis Plus. I would try to get ARC working and connect the Oasis to the Zone 2 analog output. That way you could use your wireless headphones for other input sources as well.