Unless he was using the memory of felwinter, it won't allow the super on the shield to charge. I got a message from someone the first time I did it right after that strike first came out calling me a noob, basically along the lines of not knowing how the mechanics worked. I then had to explain the artifact that I was using and then also had to mention how I had 2,000 more grimore than him. Wasn't really sure what triggered him either, I put it down after I saw the super not charging. I maybe had it for 10 seconds.