Gauci is Adelaide's first choice keeper, is 23 years old, and is a full Australia international, so will command a significantly higher transfer fee. It's a completely different signing - a back up senior squad keeper (which we absolutely don't need) rather than a young prospect.
Agree there is / will be, a definite premium on young keepers who tick the HGP box.
None of Scherpen, Verbruggen or the new Aussie lad will though, as all signing too late to meet the criteria.