People are too proud to admit that they were wrong in this case, especially when it involves Subban.
Watch the replay in real time. Both men reached for their helmets, but their momentum brought them together so PK started swinging - it all happened so quickly that even I, as a viewer, had to re-watch that portion of the replay several times to get a full idea of what was going on. At first glance, it did look like Subban jumped him, but after that, you can clearly see him reaching for his helmet.
I don't blame Lupul for being upset either because it happened so fast. He went to take off his helmet, but unlike Subban, he kept going for the helmet - either way, it happened so quickly that there's no way Lupul could have gotten a good idea of what happened.
I like the guy who made the analogy with the beer can - same deal, but nobody will listen to this post because, as mentioned, it involves PK Subban, who is universally wrong whenever he does anything.