Visa’s for Thai’s are difficult to obtain generally and unless she’s a certified caregiver it’s unlikely. It’s a daunting task to get a fiancé or spouse over as is.
There are a lot of qualified Filipino caregivers in the US already so you might look into that.
Don’t mention anything about employment unless applying for a Non B. Usually people come in on visa exempt and the school will do the paperwork and you’ll usually have to leave the country (usually to one close by) to get the correct visa. You’ll also need to have your documents officiated in your home country. The process changed somewhat recently. I’m not sure how it works specifically anymore.
They’re probably assuming you’re working illegally while living in Thailand on tourist related visas/exemptions. Probably should get a proper legal longer term visa solution. There’s visa agencies in Pattaya that can probably get you squared away for a price.