Didn’t islam have to have special religious scholars for figuring out tiny things?

At least in theory, Islam is traditionally adhered to as an all-encompassing lifestyle. As such, it’s unsurprising to find rulings on the minutia of affairs.

FWIW, deriving new religious verdicts and/or refining the old is a continuous effort as new issues/situations arise.

I feel like I remember them having to be called in to issue a special ruling through the Quran that a religious building could be entered temporarily by the police to end a siege between them and some other group.

Perhaps you are referring to issuing a so-called ‘fatwa’, which is basically understood as a religious ruling derived by an Islamic jurist on a (pressing) matter.