Cosmick and
myself have already given more examples of DC having indirect lighting and bouncing lights though. DC definitely has GI and it isn't just a case of a real-time day to night transition when referencing this tech.
That DC gif was taken from a very early morning time setting in Canada, and it's only at this specific length of time where the game gets this blue tone. It doesn't have much to do with the area being shaded from the sun, it's actually a completely different color tone/tint from a midday shadowed area and only found in the early morning and late evening atmosphere. That morning cold blue tint is also found on the Norway track and it's a fairly accurate representation of lighting, color, and atmosphere to its real life counterpart of a similar hour; here's a comparison.
IMAGE
Here's a midday comparison of Canada. Color tone, lighting, and atmosphere effects are still spot on and this is a completely different time setting, the shaded areas in no way exhibit that same cooler hue level as the norway morning comparison.
IMAGE
Regarding the ACU comparison, ACU has the cooler temp (and very blue-ish) in shadowed areas that you speak of, it's even more pronounced than in DC and this is during a very strong sunset time of day.
I'm not seeing the inferior lighting of the open environment in DC that would lead you to believe DC isn't using GI when comparing it to ACU.
*GIFS*