Curing Cortana's Rampancy

Does anyone think Dr. Halsey could have cured Cortana’s rampancy if Chief had gotten back in time? I ask because he had the opportunity to bring her back if he had left with Infinity instead of staying to pursue the Didact on Requiem. Of course, Del Rio would probably have taken her away for final dispensation if the Chief had stayed, but if not, was there a chance she could have been saved? Or was this just a desperate attempt by the Chief to convince Cortana (and himself) to continue to press on?

Lore regarding AI creation and death has been somewhat expanded upon, but after “Saint’s Testimony”, there is a lot of room to expand further. I mean, maybe the 7 year lifespan was originally a hard cap. But with increased development, perhaps the UNSC made the decision to keep the cap at 7 so that AI wouldn’t be able to rise up against their human creators (so much for that plan).