Stringfish... any tips?

I've been trying to catch my last fish, the stringfish (southern hemisphere). I'm up to well over 200 fish bait with no luck... just a million black bass lmao. I'm casting just above a waterfall, and I even made a third level just to fish up the top of that.

See, I spent all winter trying to catch the coelacanth when it snowed, until I discovered their instructions are a lie and it's not all year round! Caught it in under 30 bait the first time it rained, but had driven myself batshit crazy trying to catch it with hundreds of bait before that.

Just wondering if there's any special trick or trap with the stringfish, or shall I just keep on until it works?