The revelation that Krumwiede falsified the Forsythia cure puts a scene where he refused to give an infected friend Forsythia into a whole new light.
The main film page mentions a Flower Motif of yellow flowers whenever there's a personal loss or tragedy. Krumwiede claims to have been cured by Forsythia, which is a yellow flower itself.
To add onto this, in the language of flowers, yellow flowers are classically known to mean betrayal. And Krumwiede's claim about Forsythia being a cure can be seen as a mass betrayal to everyone who reads his content.
Since Sun Feng's village used the placebo, they will assume that they are vaccinated. If they return to their daily lives, they will contract the disease and everyone, including the children, will die. Moreover, Dr. Orantes will have no idea where the village is since she was blindfolded and rode a car with the windows covered, so it's highly unlikely she'll be able to get there before it's too late.
When Doctor Mears gets sick in her hotel room, she immediately asks for the names of everyone who has ever cleaned her room or brought her food. Even if she gave it to just one of them (and not the other way around) it's likely that, due to the high communicability rate of the disease, and the fact that hotel staff serve multiple rooms, nearly everyone in the hotel has now been infected.
Krumwiede says that the real cure could have bad effects and cause death further down the line. He's supposed to be grasping for some justification to explain why he would lie about the cure. However, since the researcher injected herself to make a cure without clinical trials, he could possibly be completely right.
In a fridge logic-y sense of fridge horror, Dr. Hexall infecting herself to test the vaccine is treated as an awesome and heroic moment. In the film, it works, and the vaccine is able to be fast-tracked, saving millions of lives. But clinical trials exist for a reason- if the vaccine hadn't worked, or caused severe side effects, the scientist making the most progress is dead, and the setback could cause millions of deaths, instead.
