That's my thinking as well. We can easily see Will believing his dad OR Sonny did it to prevent Will from losing Arianna. To me, it showed on Gabi's face that she finally realized how Nick didn't really love her but was just using her to hurt Will and Sonny. Gabi not only was devastated at the realization but, knew that if she just refused to go along with Nick, he'd talk about the ladies' attempt to drown him. The only thing I've liked about this w-a-a-a-y too drawn out SL is that the Wicked Witch (Nick) and the Dumb Bitch (Gabi) will both be gone at its finale. In other news, a new (hot) actor is set to take over the Ben role - although there was nothing wrong, IMO, with the current Ben.