Personally I wouldn't bother with the lounge, as you say the connection is only 2hr 15mins., bearing in mind you will have to be at the gate 40 minutes before departure of EK 17.

If you arrive at an A gate and your onward flight leaves from B gates that is another 20 minutes off the available time in the lounge.

I would just head for the nearest coffee shop to your departure gate and pitch yourself there