Thanks @jurgenhaas for the question.
We recommend installing and configuring a Janus server for WebRTC Gateway. If you need your own STUN and TURN, you should install and configure Coturn.
We do not recommend installing Janus and Coturn behind Apache proxy or any type of proxy as we haven't tested that configuration. If you find something in the Janus or Coturn projects that can support it, you are welcome to try.