The *smart* thing to do would be to quarantine the dog and observe it for 21 days. But the health official wants to look like he’s doing something useful so he wants to kill the dog. The thing is, as I understand it, they can’t kill the dog and then examine it for Ebola, like you would kill an animal and then examine its brain for rabies. The Ebola will not show up in the bloodstream (I think) until it’s symptomatic, so killing it before symptoms appear will tell you nothing about whether or not Ebola can be transmitted easily between humans and dogs. (Which we really do need to know.)
If you take samples periodically, virus might eventually turn up if the dog is infected. If signs of virus don’t show, then antibodies against the virus might be found, since even an asymptomatic dog will eventually produce antibodies.
It takes about 2 weeks to mount a good antibody response.
If the dog did not have contact with her when she was symptomatic, there is not much reason to think the dog caught Ebola. There is also not much reason to think the dog is contagious even if it did catch Ebola, since dogs do not show symptoms.
The dog just needs to be quarantined for a while, until it tests negative after 21 days, or it shows a good antibody response.