I couldn’t find much info doing a search - was the shooter not an immigrant and he is wrongly implying he was? Was it a different motive than what he implied?

From his wording in this clip it just sounded like he was saying “Canada is a peaceful place, so if you’re going to move here then don’t bring violence and problems from your country with you”, which seems reasonable to me. I didn’t see him say anything like “all immigrants are dangerous”.