Although there is a comment on the Channel 9 link, from someone at the Ballarat Aeroclub that the ceiling was 1500'AGL at the time of the accident.
If you look at the WAC you can see that you are crossing the tip of the great divide in this area. The area is about 500' higher than Ballarat, this hill might be 800' higher.
I have driven the route often in bad weather and it is very common that the weather at Gordon is worse than Ballarat, with low cloud and drizzle. There can be significant differences in weather from one side of the range to the other, depending on the wind direction.
Ballarat TAF doesn't mean much away from the airfield, you need to look at the Area forecast.