The thing is, the TAC teams and VFL sides are constantly scouring their areas for the likely talent, so it becomes extremely unlikely that anyone will bypass those levels these days. The pathways are heavily watched.
The wildcard - where perhaps it could still happen - would be remote leagues in WA, NT etc. But there are factors working against those boys, mainly the desire to have seen the kids in structured fitness programs etc.
This, mostly.
There are exceptions - some TAC sides do selection badly through favouring a particular region or having one all-powerful list guy who plays favourites with players/feeder clubs or similar. Bendigo is/was notorious for that, and hence why Crammeri missed out completely on the TAC system and had to take the slow VFL route. Hopefully as the TAC Cup gets its ■■■■ together this will happen less.
Other case is a talented kid who lives on the fringe of a big zone - again Bendigo is the classic case in that a big chunk of their zone's population is in Mildura which is the best part of 4 hours drive away. Getting a kid to commit to that sort of travel on top of the lifestyle/professionalism requirements demanded of someone on the draft track is a big ask. Many simply can't be bothered (remember, only about ~10% or less of TAC players get drafted after all) and just settle in playing local footy with their mates. Some will try the footy route again when they're a bit older and maybe conscious of missing an opportunity, but it's pretty tough - they'll often be out of school and have work committments, plus drink/drugs are a bigger thing, they'll often have stopped growing and let themselves go physically a bit by then, and the coaching pathways for early 20s blokes are not as good as the TAC system. This is the Duscher story as far as I can tell, talented kid from the fringe of a zone, not overly fanatical about making the AFL in his teens, didn't commit to TAC footy, changed his mind in his early 20s and made the move to VFL, and is probably earning perfectly decent $, but hasn't quite made the step up onto and AFL list.
But the exceptions aren't as common as you'd think. Frankly a decent (not standout) TAC player would be one of the top players in many local teams, and that's purely on talent. If he kept his fitness together he'd be able to run most country footballers into the ground and just do what he liked later in games especially. Most blokes like this get found, and if they don't end up in the TAC then it's because of their own choices.