Ladies and gentlemen, the most inaccurate briefing in the world.
So Spring Cave is close to a hot spring, so there should be lots of Fire-types. Makes sense, right? Now let's see what's actually in Spring Cave. Cubone, Baltoy, Snubbull, Meditite, Trapinch, Haunter, Wormadam-G, Aron, Cacnea, Onix, Beldum, Paras, Zubat, Cranidos and Ekans. Not a single Fire-type in there. Sure, you run into two Slugmas, but those are only in a cutscene. For the rest, if anything Sunflora has a big advantage with all the Rock- and Ground-types around. (Which does not prevent this episode from being really, REALLY hard, for the record. The few Poison-types there are can potentially OHKO you unless you're at full health, and Sunflora is just so weak.)
Chatot needs to lose his job over this. I'm paying so much money to the guild, they SHOULD be able to afford a better head of intelligence, right? Not that Wigglytuff is any better. Dungeon's (allegedly) full of Fire- and Poison-types? LET'S SEND IN A GRASS-TYPE! I don't care how competent Sunflora is, that's some Ash Ketchum-level shit right there. It's only a marginally better idea than President Donald Trump, and that scares me.