Assuming the jail term was set in Pattaya, a correct name and an ID number could potentially be searched at Police computers here through a lawyer with suitable sworn permission from you. That would cost you. However, not being here puts you at a distinct disadvantage as does the fact that she is your ex-wife - e,g, do you have any legal right to ask about this through official channels ?. I would simply try to get a family member to clarify. They should know.