Ultimately, though, this is where we're both wrong. We're both coming at the argument here through logic when the opponent is wholly illogical.

You're right with the first one and "the second you admit to being the bad guy, the opponent will go to HR and get you punished for defying them...but truth be told, they probably already WENT to HR, and in an HR case, because they're higher on the progressive stack they just GET TO WIN. You can show them acting like this in Macy's window, right in front of every HR employee in the company, all of whom visibly see them as the aggressor in the scenario, and HR will STILL take their side. They'd have to- HR will take the side of whoever will be more costly in a lawsuit if they sue, and more importantly, they'll discriminate against the person who won't cause them to lose their job if the person files a discrimination lawsuit. The mere threat of the TRA suing will make HR and anyone they please's head roll, but if you sue, then you WILL lose in court, and even if you win in court, the "court of public opinion" will take the company's side. The HR person might even get a promotion for "this cissie was sooooooooo MEAN to me for oppressing us for fighting the lawsuit filed by this poor innocent trans cinnamon roll who's just inherently incapable of doing nothing to no one, honest!"

Likewise, your "If I don't get my way I'll kill myself." "If you don't stop threatening to kill yourself I'll kill myself" logic fails when you remember these people are cluster B assholes and hypocrites. Even using a suicide gambit against them won't work because they truly don't care if you hurt yourself, they'd WELCOME the world losing someone who dare defy them, and it's okay if they use the arguments we're claiming against anyone else but not if anyone else uses them against that person.