It is necessary for them for Jake to be at the function tomorrow.
Is the above sentence correct if I want to say that "for them it is very important for Jake to be present at the function tomorrow"
And by "them" I mean the people who are organising the function. And in the above sentence Jake is a famous person who is going to be the chief guest of that function. So for the people organising the event, it is very important that Jake is going to be at the function.
And could provide some alternative ways to covey the same meaning?