no, hypothyroidism is not an indication for obesity surgery.
Correcting the hypothyroidism may help a little, but the hypothyroidism is not likely the only cause of the weight. It is harder, however, to lose weight with untreated hypothyroidism.
Also, most surgeons would not do the bariatric (weight) surgery until the thyroid is corrected.
You can call your insurance company and probably ask this question. I know a fellow employee (obese and hypothyroid) looked into this with our company provided insurance and that particular company requires people to attempt a hospital based weight loss program before they will approve gastric bypass. I've had pretty good luck maintaining by (normal) weight but I do have to eat a couple hundred less calories per day than the charts say I should be able to eat and really keep my exercise regularly or I can put a couple pounds on really fast. My thyroid has been stable on Synthroid for many years now.
I just thought that I should also let you know that my BMI is 43. I am not sure if that is important but I though it might be.