And if she did, and her blood is tainted with Ebola, it creates a problem for everyone she came in contact with.
This is exactly why the 21 day quarantine at home is a good idea. If she had "a sudden massive heart attack" or whatever at home, health care professionals would know what they're dealing with, and the public would not be impacted.
I do not understand what she was doing at a hair care salon, assuming this story is true.
Ebola replicates in organs--liver and spleen, mainly--not in blood. Even when patients are severely symptomatic, it can be days before there is enough virus in the blood to detect with a blood test. I doubt a woman who is asymptomatic (who probably has never been exposed in any case) is going to give Ebola to anyone.
She tested negative, anyway.