Sorry you are having trouble with Google Flights. I do see discounted dates. There might not be an many as ITA Matrix displays available, but I do see some.

I didn't link to the airline's website because it's usually easier to search around for different dates using Google Flights and the big issue is that most airlines, including Etihad, don't allow deep linking to an actual flight search. Your link doesn't go anywhere because I don't have your session data. I see either a white screen or HTTP 503 error.