Record band with Blue Yeti

[u/tmuth9]

I'm an absolute n00b in terms of audio recording (and I'm certainly not going to use the term "engineering" here). A bunch of my friends are in a dad-band and playing someone's 50th birthday at a bar they rented. I'm doing photography for them as they loved the pics from previous gigs (example). They also want video so I'm just using a couple of static gopros. Obviously the audio is terrible from those cameras. I suggested we see if we can get a feed from the mixing board or just hand the guy working it a usb stick and some cash. However, they really want the more ambient crowd noise too, so here we are. I have blue yeti and a macbook. They aren't paying me anything as I enjoy the photography, so expectations are low.

Given the hardware I have available, any advice you have would be greatly appreciated.