I played at a prerelease event and opened QGJ in one of my boosters. Played him a bunch as well and we played exactly like that, each die can trigger him and you can do them all in once action, one by one. There were no FFG reps there but all of us are certain that is the way to play him, no doubt.
It sounds powerful but you would be surprised how easy he is to counter, especially once he is down to zero shields. Then, you have to waste at least one die shielding him before his ability works. The opponents attack him, of course, and that keeps him shieldless as well. Meanwhile, you're churning out shields while they are hitting you with 4-5 melee/ranged damage each round. You're not using your dice for resources, etc.
Overall, he is good but certainly now overpowered or broken.