In trying to get a perfect score on this case I also didn't do the cone of shame, got a score of 17 which was silver rank and an extra mile. Did another run reloading the same save except gave the cone of shame, otherwise all the same answers as previous, and had the glitch happen. I ended with...
I found a bug that seems to happen if you both give zwelious the cone of shame and then talk to Scarlet about its underlying condition? Just after telling her what you think is the reason he always "runs cold" the game resets back to just before you invite her in to see him once you decide on...