Hmmmm—

Why DID Lady Gisela test Keefe twice to be a conjurer?

Is it because SHE is a conjurer?

***SPOILER

Lady Gisela drank some sort of quintessence or shadowflux to make her baby uh better?

So, to make sure it worked, maybe she wanted to test Keefe? To make sure that he did not get her genes and was going to manifest what she wanted.

So to make sure, she had to test Keefe and see if her "experiment" worked...