Here's another approach. Film a song that's sort of a signature for the band - a song with a similar groove to other songs they play. Then shoot close details from other songs - hands, faces, feet tapping - and splice them in here and there over the full length song you chose for your edit. It's really easy to take a 5 second clip of fingers on a guitar and use the mouse to stretch or shrink that clip to match the tempo of a different song, The only problem with this approach is that you never actually get a close up of the singer singing, which is why you need a dedicated telephoto shot of the singer.
A better approach would be to bring a friend (or pay a teenager) to hold the Sony camera still for the wide shot while you shoot the details with the FZ. The details bring the viewer "into" the video, rather than leaving them as a distant spectator. Or, if you don't have a dedicated telephoto shot of the singer, shoot the singer with the FZ and then shoot details from other songs. This would mean choosing the signature song before the shoot, which you can easily do by researching the band on Youtube and finding their 'hit' songs that they always play at shows.
Yet another option for a venue that's not too rowdy - get a mini tabletop tripod for a phone (leg spread is roughly 6 inches, height is maybe 3 inches) and place it on the front edge of the stage, aimed at the drummer. Now you have a third angle to use for your edit.
In all these cases, if you're shooting 4k and rendering to 1080p, you can do zooms in post, which helps keep the energy up. In the past, I've taken the wide shot, zoomed in to 200% (in a 4k timeline) or 100% (in a 1080p timeline where you have to reduce a 4k image to 50% in order to see the entire frame) and then start at the left side and do a slow pan across the stage.
