You can totally get a perfect score in the SATs and have bad spoken English. Having trouble speaking a language is only loosely correlated to being able to understand written language, especially when it’s language of tests. People who have gone through learning a second language seriously get this.

The SATs are also stupidly easy compared to entrance exams in any other place on the planet. If you are gifted and study seriously for a week you can get yourself a very good score no problem

I’m sure that there are cheaters, but if your reference is “bad spoken English” that’s not at all conclusive