Angle of entry is extremely important as well. Given a very shallow entry it's likely to burn up before getting low enough to damage anything (or at least significantly shrinking in size before it impacts/explodes), or even just ricocheting back out.The variance you're talking about in distance is showing EXTREMES. It'll almost certainly happen somewhere in the middle of that (basically it'll miss).
As for the damage difference there's more to how much damage is caused than just size ... composition has every bit as important as a role. So while this asteroid might be five times larger it also is significantly more ice.