Getting charged with tampering is much, much easier than successfully tamper. If he wanted to scare Elison publishing some dirt or sending texts is not going to do it - feds have much better ways to scare people into cooperation. And his very expensive lawyers told him as much, I am sure, because every lawyer would. But he probably decided he knows better.

But the payoffs are very much asymmetric. Getting convicted of tampering adds a few extra years to his sentence which will probably be more than his life anyway. Successfully tampering with the witness may avoid the conviction in the first place.

Except there's no chance of successful tampering the way he did it. Never was. Publishing dirt on one of his co-conspirators is not going yo negate his conviction.