search this page and other and u will find a great deal of discussions on this topic. in general so much depends on age of ur husband, any pre-existing conditions (which will be excluded from coverage), and other plan benefits offered. Many misinformed will offer advice and make claims about spectacular coverage for inexpensive premiums-- simply not possible-- the devil is in the details, review carefully any plan's benefits and see they work for you, and what deductibles, limits, etc are included. as u may know, BUPA, in Thailand is no more-- it is now Aetna who, like many other carriers, will not even offer coverage to those 65 and older, unless you were with them prior to age 65.
I think you made the wise choice--the idea to file appeals, and "stand your ground" ( not even sure what that means--?? argue, become angry and abusive, or just refuse to budge until they have u thrown out or arrested?? then try to return to submit ur forms and see the reception u might get?)
like u shared, u can only roll with what is demanded, over 20 years of living here has shown me, and many others clearly, you RARELY, get too far with taking on the aggressive/assertive role-- oh, yes, you'll hear this guy and that claim to have done so, and "showed them", but most such stories are just pure bs! it makes some feel good to act tough. you made the best choice for your long term interests in working with that office.
in chiang mai, penalty was usually 1900 baht-- and it was on a paper receipt small doc attached to a page in my passport , indicating when next 90 is due. 20,000 sounds like fine for overstay??