Receiving an invitation to an IT event to facilitate obtaining a visa. Is there any experience?

Question

Emigration and immigration

Do you have experience of interaction with organizations conducting events? If yes, with what?

Answer 1

about the IT event is not even funny

Answer 2

Absolutely nothing matters. Everything is random there. I witnessed how in a married couple one was given a visa, and the other was turned away. Although they showed some invitations there.
He himself received a visa to the United States 4 years ago with a pristine foreign passport received a week ago. Nothing was asked during the interview , that is, nothing at all . They just took it and approved it silently, although the invitation was with me, but I didn’t even have time to get it. And in general, I did not manage to get a single document, except for a passport.
At the same time, literally a couple of people before me in line, a man who has been traveling to the States all his life, has heaps of some kind of international visas, permits, heaps of papers, was refused.