I appreciate this is a complicated thread. But I actually get where the op is coming from.
On mn a tread can run one way or another depending on how the first op is taken.
Putting all other things aside, can I just comment on making the ds say sir repeatedly. I actually think this often is nasty, can be gaslighting.
I had similar recently, as part of a much bigger complaint. Mine was with a hospital who had failed to notice a health condition, and just treated me quite badly, losing my notes, being dismissive, discharging me etc.
Eventually, after a long battle, I had The woman from pals, who incidentally is there to protect the hospital, not help the patient as such, she's like HR.
anyway, after innumerable emails and stuff had a phone call with this woman she was just really off right from the start. one of the Doctors had a name that's difficult to pronounce. I was there struggling to speak, struggling to remember what happened when. I'm in pain, almost crying, and 6 times she kept insisting every time I says his name dge interrupted and corrected me 'it's Mr xxxxx'. After I got off the phone I remember thinking that it was just really nasty, unnecessary, bullying actually.
If I'd wanted to, I could've referred them to person A person B , Dr A Dr B, if I've chosen to, it it's none of her business.
sometimes you do get someone who just uses their position, in a really under-hand, nasty way. It's aggressive. It's trying to control the person. It's basically soft bullying.
this thread reminds me of that. The school were very heavy handed, I think they know they've not behaved well overall. But that final bit, the bit where they kept insisting ds said sir, again and again. It's overkill. I think the teacher who did that was just trying to exert their power. But it's got a nasty tinge to it, that I really just don't like. When I read it, it made me wince.