He was being sarcastic. Isn’t that obvious ?
Is it? Over 200 hundred people died on that flight - want to ask the relatives if they thought that was just being sarcastic?
No, his words were two abominable words that no decent person should utter for fear of being taken seriously. I don’t reverse engineer people’s words. If you pose as a terrorist, you will be treated as one. If you joke by uttering terrorist prayers, you will ejected from civilization at the earliest opportunity.