As an English atheist, possibly surprisingly, I think Islam is right regarding interest. Unfortunately wrapping it up in mumbo jumbo doesn't give it any credibility. Also it isn't really related to the article.
a) growth isn't required in all economic models so inflation isn't necessarily valid.
b) goods and services are perfectly good interest. Not that you'd have to borrow it if interest wasn't profitable (it would drive asset value down).
c) risk is irrelevant if lending isn't required.
you're too in the bank and growth model mindset. It doesn't work like that everywhere.