I don't understand how your wife changed her sponsor... To do that, you would need a contract attested (i.e. stamped) by the Ministry of Labor, medicals and various other supporting documents... As far as I can tell, your wife is currently working illegaly in Qatar and cannot, therefore, claim any benefits under the Labor Law... As a result, as rej2k7 correctly says, she does not require an NOC and can easily accept any job that is offered to her. Until she does get that job offer, consider taking her under your sponsorship. You should have no problems with that, as long as your income is in excess of 10,000 QR/month. Otherwise, she'll have to leave the country when her visa expires and you'll have to "re-import" her.