USA, Canada /
Getting my Polish fiance into the US [16]
He should list you.
No body will believe him, that he has money to stay in hotel in the US.
Listing hotel as a place to stay will end with no visa.
He even should not mention that he is looking for PhD program.
Tourist visa is for tourists and for nobody else. A person looking for school is not a tourist. That person is a potential student and should apply for F-1.
He should be as natural as possible.
"He is going to visit his friend who met in ...... and she invited him for vacation to the US."
Your letter to him with invitation may help.
Just regular letter: Hi, how are you? Are you going to visit US this year. If yes let me know I will accommodate you for that time."
He should keep the envelope with your address on it.
They will also be looking for something else.
Not only who is in the US, but what keeps him in Poland.
Document from his employer that he works full time is really good thing.
Even better would be if he can show that he just started PhD program in Poland.
Being a student is really good help.
His answers in embassy should be short, in topic and natural. He can't think what to say, because it means that he doesn't know answer and prepares it.
One warning.
DS-156 form has a question about family in the US. Fiance is also mentioned there.
If he checks that his fiance is in the US, he is not eligible for tourist visa. They will advice him to apply for K visa.
if he does not checks, he will lay which means 10- year ban if officer discovers that his fiance is in the US.
So. You are his friend and only friend met someday somewhere and nothing more.
And shut up about marriage, girlfriends, PhD programs and any other type of schools.
By the way.
I really encourage him to read everything what is on this page
go2usa.pl/poradnik-turysty/index.html
Some technical information are old, but other information, what to do, how to prepare himself, about body language are perfect.