Snake handlers can point to one scripture that supports their practice. Snake handling preacher gets bit and then dies because he refused medical help. Relied on his God to save him instead. So now he's dead.
JWs can point to one NT scripture to support their belief. JWs refuse blood transfusions, relying on their God to resurrect them in a paradise earth later. Many JWs, including children, are now dead.
(If there is a difference it's that JWs are worse in that they allow their children to die to prove the adult's faith in their god)
Engage a JW and get them to critisize these nutjobs, and then after you can slam them for being exactly like them, you can watch a JW slither away just like a snake after biting a Pentecostal...