I didn't ping it when I had the Energized blocklists, but after reverting to the default (Large) list, it's fine, Ping responds back with an external IP. I was using Energized block list for 2 months and now I can't even add any of their lists, I don't know what's going on. I can't even access any of Energized lists on their website, so weird.BTW you said you whitelisted "s.amazon-adsystem.com"
So what happens if you ping it from your PC? How does it resolve?