This is the kind of thing you can google in fact. Qatar have said they would allow an Israeli team to participate, which doesn't answer the question of whether they would allow Israeli supporters into the country
Well that's a whole 'nother problem right? What international sporting organizations are NOT corrupt? The Olympics, FIFA, F1 all are, anybody else? Maybe it's just sports orgs that keep their headquarters in Europe?
Heaquarters in Switzerland (or Monaco), it's kind of our speciality you know?
Anyway, the reason international sports organisations are so corrupt is because they are private sector monopolies, no oversight and they can do what they want.
Which brings us back to the question of countries like Switzerland, which are very, er, relaxed when it comes to regulation of foreigners bringing in pots of money to spend in the country.