Some random observations:
1. I don't know what's in the specialty course, so I can't comment on whether it's a good value. I doubt it would be recognized by places like Roatan that require training, partly because their training emphasizes how not to hurt the reef while spearing lionfish (only with a short pole spear).
2. No certification is required to hunt them in Florida. I'm not even sure you need a recreational fishing license to do so.
3. As to the need for specialized training, I'm skeptical. Lionfish are incredibly easy to hunt. They are easy to spot: they look like a cloud of fins and spines. And because they are confident about their invulnerability, they let you get real close. The only "tricks" are to approach very slowly and shoot from point blank range. Nothing someone like
@Johnoly couldn't teach in a few minutes.
4. As to whether the hunting is having an effect: I think it can have an effect in coastal waters shallow enough for hunters to reach. However, lionfish thrive at depths much deeper than divers go, and I doubt those (presumably larger) populations are feeling any pressure from hunting.
5. They are delicious. When we were in Roatan, our hotel cooked up my catch each day I brought some back. In Antigua, the cook on the boat made ceviche from them.
6. I am in the "don't surrender your catch to sharks" camp, but the sharks I've encountered so far have been discouraged by gentle poking. I might lose my convictions on the subject in the face of a determined shark.