Alternative explanations could include the following: Among the ranks of JWs, many dkready have ore-existing mental illnesses including depressive outlooks or that the JWs minority status makes followers vulnerable to stress caused by being outsiders from wider society.
Most men who commit suicide don’t have any known mental illness.
One factor that would come into play is occupation, for men working in construction the rate of suicide is much higher. I expect the JWs would over represent in these jobs compared to the general population, certainly in Australia they do. So we should probably expect a slightly higher rate, at least in Australia.
But like Steve said, virtually impossible to know with so many factors.