I can also confirm this works, and I experimented with my previous question a bit. Out of 5 attempts, breaking the glowy bit does revert the head behavior to normal every time. However, this lets you get a bunch of free hits if you slide under and don't initiate the QTE, as Corpius just sits there with its head in the same spot, as you do with any other Corpius fight.

That's awesome! If you were to destroy the glowing red ball (to get more missiles) does that reset the AI? I presume it would since Corpius would undergo a phase transition, but was wondering if you'd tested that.