Tapping Sound from church speakers as aux input for streaming

Our Small Church has a PA system with controls in the front of the church. Because of COVID-19 we have been streaming services. Our Streaming is set-up in the Choir Loft with no direct access to the PA System in the front. We have been using a separate wireless system for streaming with sporadic results. There are speakers in the Choir Loft on a 70 volt line. Is there a way to tap into that resource and convert voltage? wattage? ohms? to use as an Aux Input Line to our mini streaming mixer?  The distance from the PA System to Choir Loft is 80ft. We have limited access to any controls because it cost an arm and left for the Audio People to come out and re-adjust. We can only control Master Volume and turn Microphone on or off.  Need a suggestion, driving us crazy for the last 3 months.