This a explanation, not a solution?
I know this was almost four years ago, but are our solutions archived? I was just thinking of this glorious day :)
You can view your own submissions by going to the problem page and clicking on "Submissions" (above the code editor).
Does the coupon code still work? It isn't working for me.
Learneroo coupons are offered on rare occasions, but they generally expire within a short time.