Did he shout "Am I Da'ash?" (Ani Da'ash?)
or, did he shout "I am Da'ah" (Ani Da'ash!)
In Hebrew - it's the same sentence, only the intonation is different.
As the article pointed out, he was an Oleh (new immigrant) from Dagestan. According to people who knew him, his Hebrew was less than perfect.
Sorry, but this doesn't add up. So, ? or !....unfortunately, we'll never know.
He said "I am Da'esh" BEFORE reaching for their gun.
I'm pretty sure the IDF and police could understand the difference between a question and an interjection, and especially within the context of this individual asking IDF soldier for their ID's and reaching for their gun!