Hi
I too have 2008 3.5 Vellfire which is also 4WD, and when I read your article I was concerned that my car could also be affected. So I did some research online about the 2GRFE engine and have found, they have been around since 2005 and the early engines did have a rubber hose fitted to the rear bank VVTI line and this would be visible. Your picture shows the rear VVTI line and there is no rubber hose, same as mine, so its should be fine. If you check out ebay someone is selling a 2GRFE engine for 2005 ? 8-2015 Mk2 Alphard. There are some pictures of the engine and it shows this one has a rubber hose fitted to the rear VVTI line. As for engine oil coolers on 3.5 Vellfires/Alphards S2 I don't think they were ever fitted, but other models in the Toyota/ Lexus range with this engine were, notably the Toyota Avalon from America there's a UTUBE video on how to remove this engine and the guy mentions the rubber hose and how it can leak.