I think that is the key issue. Nobody wants a hooligan in their syndicate and unless they know you then they will be extremely sceptical. They are taking a risk bringing people in. Nobody wants to lose their hard found stalking because of one idiot.Stalkers tend to be very reticent with their land and who they let on it, some with very good reason.
Not withstanding that there is a hoarding instinct, or as i like to express it, a lot of recreational stalkers want to run a zoo. That precludes bringing in other people as there is a fear that they will shoot the prime bucks. All at the same time as there being too many deer.
There isn't really an easy way to get into the stalking network which I think is one of the issues. It is by it nature a fairly remote, solitary pursuit. So you dont exactly meet lots of stalkers. When you do then they probably have similar issues ie they could do with a bit more ground not less so they are not going to give up their leads to someone else.People who've taken a long time to acquire their shooting aren't going to share with someone who hasn't.
The suggestion to do other things I think is a good one. I got into stalking as I shot clays. Turns out some of the guys stalked. I just tagged along and eventually started stalking. They knew me, they knew I was safe with a gun and they knew I wasn't a cowboy but wanted to do an apprenticeship. Boxes ticked plus I had some "references" in the network when I wanted to get into other syndicates.