The version linked to above is a handwritten draft copy, with some annotations by someone (perhaps Grothendieck). A typed version does exist which does not contain the preliminary material in the first file. The date of the official thesis defense was 22 May 1975, with Jean-Louis Verdier, Henri Cartan, Laurent Schwartz and Michel Zisman as well as Alexander Grothendieck as the ‘jury’. It was a ‘doctorat d’état’. The link to her thesis contains other material, including a collection of remarks by Grothendieck on her work as well as two papers by Sính related to the subject of her thesis:

The first appears to prove that every 2-group is equivalent to a strict 2-group arising from a crossed module. The second calls a symmetric 2-group a Picard category, and calls a Picard category restrained if the braiding$B_{x,x} \colon x \otimes x \to x \otimes x$ is the identity for all objects $x$. It then proves that every Picard category is equivalent to one arising from a 2-term chain complex of abelian groups.