I was actually originally going to have Roger do some kind of "remote override" using his wrist display deelybobber, but it would have taken at least two panels, if not three, to "explain" that.
It was easier to just have Roj slap some control on the suit itself. And if we need to "explain" that, well, it's a prototype suit, not necessarily intended for actual combat, and thus has more safety features and failsafes built in than a "production" unit would. One of which being multiple "get me the heck out of this thing!" buttons, both inside and out. (One can presume there was one on each arm, probably one on the torso somewhere, and about a dozen that the pilot could reach. )