It works, as long as the failed graft branch is not already dying back. Also, that branch should have many leaves still growing below the failed graft point. That's one reason when I graft to avocado seedlings, I don't graft close to the seed/soil line, I try to graft it at the half height point of the rootstock. Then you should get 2 chance to make a good graft.
If the failed graft branch doesn't seem to have many leaves, then just wait a few months until you see new buds from where the leaves are, then its ok to re-graft again.