I haven’t been watching the trial since before lunch. But one thought I had regarding Zachry and Kenny allegedly ganging up on HGR —- I think their disdain for her is completely understandable. She’s a nepo baby and hire. She was seemingly arrogant and didn’t want to follow orders. I think most people would relate to their negativity towards her. She also called Zachry a C U Next Tuesday. She wasn’t exactly a nice person by all accounts so far. Also, it was her responsibility to handle the firearms, and it’s understandable that they all feel like she’s responsible/guilty.
JMO
I gather there was also some bad blood because of the previous accidental discharge by Sarah. Here's a text exchange about it between SK and HGR:

BTW, do we know what the previous relationship was between SK and Sarah Zachry? As I understand it he was the one who recommended her to be the props master.