It’s a strange reaction though. “I’m resigning.” “OK, that’s your prerogative, bye.” “Wait! I didn’t mean NOW! How can you fire me like this?!” Then make a big deal about being fired on social media. Seems to me that someone who genuinely was ready to resign would have just quietly walked away, even if they imagined it ending less abruptly. Can’t know for sure, obviously.

Resigning doesn't mean leaving quietly. Especially for a researcher ordered to retract a paper.