If you are driving a car you are good for three months on an English language license. It’s the bikers who have a problem, as many have never passed a bike test, so their car license is not valid
in some countries (Uk for example) you can get an IDP on line, and get it sent to a local address, then courier it here, takes less than a week. You don’t mention what you are driving ?
Depends what you are driving, if it’s a car a license in English is fine for up to three months, if it’s a motorbike you need an IDP so they can see if you are licensed to drive a bike. Tourists renting cars at the airport are not required to have an IDP, and you are very unlikely to get pulled over in a car in any case.
Consular officials , assuming you get past the gatekeepers , will work on the assumption that she will do a runner once she is in the US. Your challenge will be to convince them that ain’t going to happen, lots of sound ideas in earlier threads that you need to package together. Good luck.
break the bank but for something serious it expensive to provides piece of mind, if you are coming here to live different discussion there a numerous policies avail for long term expats most of which can be tailored to your needs