family visa

hi,
my wife is working in a company from the past 12 years on their sponsorship.

my kids r under my sponsorship.

now we have got the family visa.

but wife;s sponsor is not giving noc.

now i m planning to send my wife back to cancel her visa ..

1-in case if i call my wife on visit do i have to get noc from her previos sponsor ?

2- can i get her stay in qatar for 1 year with out any exit?
as with the kids it is not easy to make her stay out of qatar for 3 months after spending 6 months visit visa .

3- do i have to pay extra charges for this ?

4- or it could b done easily.

5- or any ministery could help me in this regard ?

pls help and advise coz this is really going a big favoure for me .