Don't satellites have very limited abilities to change their orbits? A request for Iran would be for Russia to photograph something when the Russian satellite is in the area anyway. Unless Russia happened to want to concentrate on something else in that area this shouldn't impede their own surveillance.

Also, I'd expect that everything Iran wants to see Russia also wants to see.

At this point, China would be interested as well. If Xi decides to get on the despot raiding party bus, he'd like to know how effective Iran's capabilities have been on US assets. At this point, North Korea might be looking south too.