what exactly are they not covering, and why? Most every insurance, including Pacific Cross, do not cover accidents when alcohol was involved, when a high risk activity was involved, like involving a motorcycle, or when the law was being broken. What did they refuse to cover exactly? No one can help you without specific details.
you need to be licensed in Thailand to do that. Also concerning your husband, any kind of commercial driving, including bus driving, is restricted for Thais only.
Yes, a medical certificate is required to get a Thai driver's license. You are being scammed though, as you can not get a legal Thai driver's license online. With these online scams you'll never know it is a fake license until you get stopped by the police, and then you can go to jail, and be deported for using counterfeit documents. Be fully aware of this.
the grey area to protect your ownership is in the corporate voting rights of the company stock the Thai partners own. It can, and is, set up so they don't have voting control of the business.
just so it is not a tour guide, as that is a restricted occupation. Each work permit a company sponsors requires what I listed registered capital wise. There is no way around that.
To get a work permit the business must have at least bt2million in registered capital, and that you hire at least 4 Thai employees you pay social security, and wages on. Then you can only own 49% of the business yourself. The rest must be Thais, and they've started cracking down on proxy Thai owners. Remember, you can not legally do any work without a work permit.