Say what you will about the Pearson Starbucks, they certainly get the job done! Every time I need a latte before a flight, the line is very fast moving (but rarely short!) I have noticed the service can be a little terse at times, but I have never had a problem with my order here.
This location definitely accepts the reward card and the phone app. I can't say for sure if you can redeem rewards here, but I can't see why not.