It is very close to it. If Buddha's actual words would have been there; it would have been even closer. Unfortunately, Buddha did not write anything or dictate anything, just like Jesus.
Regards
I read this as describing the ineffable nothingness that is the substrate to all reality. It in no way claims personhood for whatever it's describing, which is a key feature of the Islamic conception of God.
As for you're claiming that Buddha was teaching Islam and this would be clearer if we had his genuine words, this is a good example of Islam's supremacist aspect at work. It's not enough to tell people that they're following the wrong scriptures and teachers, you have to say they're following their own teachers and scriptures wrong, and you've got it right. This seems pretty arrogant to me.