I am not familiar with any law that requires an employer to pay for the time that you quit working and go smoke. If you do find that an employer is required to pay for your time away from work, you could file a claim with the Oklahoma Department of Labor. I am providing a link to the claim form below.
Brief rest periods of less than twenty minutes are generally paid time under the Fair Labor Standards Act. The employer should not be deducting pay for taking breaks. If the employee is not supposed to take those breaks then the employer's remedy is to fire the employee, not deduct pay. Your husband has a wage claim against the employer for the deducted time. Additionally, the employer seems to have retaliated against your husband for complaining of a wage violation, which is an additional claim against the employer.
Your husband should speak to a local employment lawyer about his claims. Wage claims allow for attorney fees and expenses to be paid by the employer as part of the recovery of wages.
It is unclear whether your spouse is smoking on breaks that are approved by his employer as to timing and length of break, or whether he is slipping off to smoke in addition to planned breaks. And yes, that can make a difference.