Alan Gomes wrote:

Better yet, drill the hole, then chuck a bent nail or allen wrench in a
drill and remove a portion of the exposed core. Fill that with a high
density filler. You will then not get any rot in the core. This is not
rocket science. And it's certainly nothing to get hysterical about.

That's exactly what I've done - you end up with a very solid leak free
section of deck. Its probably better than most of the other deck
fittings.