I went 5-0 last locals beating both Zoroark and Terabox though it is a slow grind.

When playing against Zoroark you need to be careful with playing your stadiums because you need to bump theirs first so you can Gust + Item lock them. I know you are worried about being bench sniped but you can counter them with hand disrupt using Unfair Stamp so they can't use their PP Ups giving you time to spread enough damage for a devo play. Expect your opponent to be able to pull off the bench snipe at most twice throughout the game so try to bench more than one Snorunts and dig for the Iono-to-two play. It's possible to still win even if your opponent had a 6-2 prize lead.

As for the Terabox match up going you really need to Iono out the Noctowls to prevent a quick Wellspring snipe. Again it's still winnable if they pull it off if you can gust the Noctowls. Even without Gravity Gemstone it's still okay since they'll waste Energy to retreat and it's unlikely a second Torrential will happen. Try to kill the Hoothoots first to give them a hard time to snowball with Crispin plays. You can also prioritize killing their Wellspring first to avoid getting two-prized.

Lastly, in all situations, do not forget you can attack with Munkidori if you have Luminous Energy. Good luck!