To deal with any trust issue, get a second opinion! ;) The problem here is, "native speakers" aren't guaranteed to be "good speakers". I have co-written with several non-native English writers because... well, their English is far better than most "native" writers. The proof is in the pudding, as we say. The only time I wouldn't trust a non-native English speaker is if they actually demanded that I trust them. ;)

When I was a student, I used to attend the English lab course (listening, speaking, pronunciation). I had to pass the exam at the end of the year in order to get the certificate. It is an important certificate that is required for the teaching of the language. Also, when I went to Britain to attend a training course, the emphasis was very much on learning the spoken language... Now, as an ESL teacher, I'm supposed to teach all the skills: reading, writing, speaking and listening. Besides, The CLT approach (Communicative Language Teaching) is used in all the ESL classes. It is a method that gives great importance to interaction and aims at helping learners develop their communicative competence. Therefore, ESL learners are supposed to be able to use the language in the classroom and outside it in a variety of contexts... As an ESL teacher, I'm using this method to develop my students' confidence and help them learn the language in an authentic context... Finally, I don't think that a speaker of any language is ipso facto qualified to teach that language. Tunisian people are required to learn French at an early age (5 or 6 years old) and they speak the language as fluently as a native speaker. If you hear a Tunisian speaking French, You will automatically think that he's a native speaker... However, I don't think that all those who are able to speak the language are also able to teach it.

i think that the matter of trust is so difficult nowadays, i mean even with native speakers u can't trust them, so how about non native. it need a long time to trust in someone. good luck