Go to the area where they've been roosting and get a comfortable seat and wait! Call very little, maybe a cluck or purr once in a while. Scratch around in the leaves like a feeding hen, and stay alert! Sounds like to me you're dealing with the kind of gobblers that will sneak in un-announced, so look alive and stay awake if you want to kill them. The reason I wouldn't call much is it sounds like maybe you've already pounded them some with calls, and no luck with that, so I'd lean towards the cautious approach and not call or very little. Just my opinion. Good luck!!