What is the role of student recruiter at business school?

If they like your CV and think you are a good candidate you do think, they will have influence with admissions committee to get you selected or is it just a tacit to get you apply?

Their job is to get applicants.

Yes, their job is to get applicants. However, I don't think they have any incentive to be dishonest with you: if they don't think that you are a promising candidate, they're not going to tell you otherwise.

Also, being a promising candidate doesn't necessarily mean you'll get an admit - that's another story...