I am a domestic student so I don't know if this applies but when I go to the application page the official letter is there. You could try reading the financial emails with a closer eye or logging into the mypurdue.
Sorry I can't be of much more help than that, good luck!
I think you should have your official letter from Purdue by now but I'm also not really sure how deferrals work. I got a bunch of emails regarding financial offers, the official letter, etc. They have a virtual visitation next weekend. Wouldn't hurt to contact them