Free: Contests & Raffles.
Sounds to me like the birds don't have hens, right? My advice stands. On May 4th this year, trying to strike a gobbler, nothing was working. As I often do later in the year, I gobbled. A bird answered, and proceeded to triple gobble for like thirty minutes. As we were moving in on him, I'd gobble to check him, and he would freak out. I'd fire back, one or two or three times. This went on for, like I said, thirty minutes or more, just a gobbling fiesta. I stopped hen calling cuz he didn't care about that. Long story short, he flew the canyon to where I was gobbling from. He didn't have hens. If it were me, I wouldn't even take a hen call out of my vest and solely gobble, since hen calls don't seem to be doing it, but to each his own. I get the safety issue, but if you're sure nobody else is around, go for it. Good luck.
Like my dad always said, 99% of all humans are caused by accident ... or was it the other way around?