In Germany (and in other countries) in the 19 and the 20 century was the custom that a name was change to a German name with is beginning with the same character . You asked if the name Leonora derived >from Leie, Seie or Gittel. In my opinion I think that the name get out >from the name that you have read as Leie that like on the name Lea. Seie is not a name as I know. And the begin letter of Lea is a L and Leonora also so you can said the Leie (Lea) is the source for Leonora Best regards
