OP's wife needs more than a Scooby, don't know if he knows either that as her husband if he does help her to eventually stay and work in UK he needs to show £62,500 in savings or get a job to earn more than £18,000 a month for her to stay with him for 2 years and 9months.
If she can get a holiday visa she will have to come back to Thailand at the end of that Visa period and apply again, if she overstayed she would disqualify herself from future visa's.