He looks like a pretty typical admit according to the COE’s FAQ:
https://www.purdue.edu/futureengineers/What%20To%20Know/Common%20Questions/Frequently%20Asked%20Questions.html
That was for 2017 and it does seem like admissions get tougher every year so if Purdue is a top choice have him get his application in early and be enthusiatic about Purdue in any essays they require. I think Purdue no longer does rolling admission and engineering in general is pretty stats aware but showing some love for the school can’t hurt.