Um.
I just stepped into this thread, and I've got no dogs in either race....and I see you being really super defensive.
You are on a UFO forum. Art Bell, to some UFO folks, was a huge celebrity. You're accusing him, a dead man, of murder.
Did you think this hypothesis would go unchallenged?
That being said, first, they're both dead, and I was brought up not to speak ill of the dead (for several reasons). Second, if it's not true, it's mudslinging. If it is true, well, he's well beyond mortal judgment; time to let it go. Third, um, yeah, accusing a worldwide celebrity of murder, even if they are dead, is a big fucking deal...especially with no evidence save the fact that he married quickly after the first wife's death.
He'd been married for a long time, and he was old. After the death of his wife, he was probably unbearably lonely. Pretty young thing pays him attention and says all the right things? Yeah, it happens all the time.