I alluded to that toward the end of my reply. A non-Muslim may start off with that presumption until he is convinced that Islam is the truth, at which point he accepts it. Once the foundation is set, it does not make sense to keep that doubt or skepticism around any longer. Why accept the religion otherwise?
> Science cannot make such statements of certainty
God is outside the realms of time and space, which are the domains of science. It is a non-question to attempt to answer philosophical and religious questions through (experimental) science.
Furthermore, it's a fallacy to break up the world into "science" and "religion". Which religion are you talking about?
> Science allows restructuring its own foundation
I don't see how that has anything to do with the subject matter, or that it is indicative that science is somehow the absolute truth, or even leads to it.
The foundations of Islam are the Quran and Hadith. Islam has immutable and axiomatic principles (e.g. God is one, Muslims have to pray 5 times a day, the Hijri year is 12 months and follows a lunar system, etc.), some other aspects are open to interpretation (contingent on having a proper scholarly background of course - a layperson cannot interpret as he/she wishes), while other aspects are left open for society to decide as per its needs and evolution of time. I read that Muslim scholars hundreds of years ago derived rulings for how to pray if we were to fly one day - they were that forward thinking, and today we have airplanes.