You want to buy "Rode" mic for audio, the go pro is great for a third angle, although, they do have fish eye look, so maybe get another cheap 4k camera for the third angle, personal I recommend the same camera as I use, it´s great for stills & amazing for 4k & hd too...
https://www.bhphotovideo.com/c/produ...hoCGBAQAvD_BwE
you´ll probably end up using it more than the big sony camcorder
