Ad units do appear differently from organic results - this was ventilated in the original case, where the judgement was that there was definitely misleading conduct - on behalf of the advertiser.

It seems that the on appeal, the full bench decided that google was actually responsible - given their algorithms were responsible for placing the ad in the context.

This doesn't seem to be quite the same as the ambush marketing you mention. That would be more placing an ad for "dell" when searching for "elegant mobile personal computer".