Well, the weight of the blade and the style of grip is conductive to a very powerful stab, it's coming from above and aimed at the shoulder and neck so the question is whether Gigue's body would have moved sufficiently (and destabilised Sigurd significantly) to offset the point so that it would glance down either his front or back instead.
Due to the position of the two fighters I believe the thrust would be coming in at an angle toward Sigurd, so Gigue moving backward would be unlikely to offset the point sufficiently, and once it makes contact with the top of his very broad shoulder the weight and power of the thrust should drive it through his armour and body. It's also at a slight leftward angle, which means that a glancing strike could offset the point into the bottom of Gigue's throat if he were unlucky.
Sigurd being pulled over is not going to be easy, all credit to Gigue's strength but he's got his work cut out for him lifting the warrior's entire body weight and armour up and then falling backwards, because Gigue's leverage isn't the best with his grip only on Sigurd's right side and one foot. Therefore we can assume that even though Sigurd will be dragged to the ground his thrust isn't going to be massively affected.
I suppose the question is which is faster, Sigurd's thrust or Gigue's grapple/suplex, they were launched at roughly the same time due to Gigue's hyperarmour delay.
