Thai Competency for enroling local Thai University Courses

Hi,

I wish to take up the Thai intensive program with Chula University and wonder whether the silver/gold/platinum certificate issued at the end of the program would allow me to enrol for Chula University local program, assuming I have a Bachelor degree from Australia.

I'd checked with Chula admin, but they said that the university enrollment requirement differs from uni to uni.

How does the university judge the prospective foreign students on the command of Thai language before allowing them to enrol into the program?

Or do the university accept only the Thai Competency Test result conducted by the OBEC?

Thanks and hope someone can help me out.