What if in the end of the DLC, phentrans had developed ONE prototype mega cure for the infection? Then, Chuck would want it for Katie, but Frank would want it for himself. --- A little pain never hurt anyone.
they would probably neither take it. you should save it so you can duplicate it and run some tests firsts before giving it to anyone. besides Frank is not a bad guy, he would probably give it to Katey before taking it himself.