Strong bench session, 107.5 feeling light is a good sign. Shame about the deads but you'll get it once the grip is sorted.
Static holds have helped me quite a bit at the end of deadlift sessions. I have used hook grip up to 200kg too but that takes some getting used too. I agree with Pull though on the possibility of not using them correctly. If they're just making the bar fatter and not improving grip it sounds like you're wrapping them over the bar rather than under and opposing your grip.