"who appears not to be motivated by religious extremism,"
I guess that depends on what you want to believe, the source I showed said he was. I don't know one way or the other but that leak sounds pretty solid to me. I do believe islam is responsible for many outrages like this one, and that fits real well.
I'll need some more solid confirmation before I accept that theory. Of course it's possible, but I haven't seen evidence yet that convinces me.
One huge question for me on the supposed White House leak is this - why would the Trump administration cover up any evidence of an ISIS link? Trump ran on and continues to reinforce America first, fight terrorism and border security. If this guy really is ISIS, it would be a huge benefit to Trump's war on terrorism. It just makes no sense they would cover up information that would benefit their political position.
Now Obama? If he were still POTUS it would benefit him to hide an ISIS link since he was so fond of telling us terrorist attacks on US soil were not a problem.