"Tell Ally that I will always value her opinion on things!"
Even though he was successful in ejecting and finding a safe place to lie low until help arrived, he was ambushed by the Teenage Mutant Ninja Turtles as he was climbing into the evac helicopter. When asked about why they attacked and killed Rex, team goof Mikey said that it was all the result of the illegal shrooms on their pizza placing them all into a drug-induced rage. The case worker assigned to evaluate the story made sure that the masked vigilantes were let off with a warning.
A memorial for Rex will be held in the comments section down below. Those who knew him are encouraged to share stories as well as sentiments. Rest in piece, you lovable fool. We will await the day that your respawn timer cools down.