Hi anut,
It's a shame that the flavour is not quite what you were going for as the cheese itself looks really good. Nice amount of blue and all. Hmmm, you could try harvesting the mould from the gorgonzolla that you are trying to reproduce. I don't make many mould ripened cheeses so I don't keep a supply of moulds at home. So, I just harvest from a bought cheese and that's worked quite well for me so far. That might be worth a try.
Also, it could be that it really requires a full 3 months of aging for the flavours to develop properly.
Still, it doesn't sound like it's too too far off. Are the undesired earth tones stronger closer to the rind or fairly equally distributed throughout the cheese? (taste a bit of rind and if it's really strong, that's probably your primary crime scene). If it's in the rind, it may be that you're picking up a wild mould of some sort and need to give the ripening box a really good clean and sterilization before the next one. If it's throughout, then I would go with your guesses of process, the strain of blue mould, or the choice of cultures.
- Jeff