Nidalee isn't the greatest teamfighter; she lacks any form of CC. Also, she isn't that tanky; honestly, think of her as a squishier, ranged Jax. She's really great in 1v1s and splitpushing, but isn't fantastic in teamfights.
Looking at your match history, you actually did more damage to champions than her by 5k. That Vayne probably just wasn't that good and got carried; no one else besides that other Gnar did close to the same damage as you two.
In general, don't underestimate the amount of damage you get from base stats. Just pulled this game from my match history as an example; I played full tank Amumu; my only "damage" item was the passive on sunfire cape, yet I still did ~6k more damage to champions than their Draven. Sure, that Draven did poorly, and sure, I didn't play great either, but the point I'm trying to make is that a full tank can still do a ton of damage with just base stats. If they're a bruiser, like that Nidalee was, she'll do even more damage. A Bruiser can still 1-2 shot a squishy carry, they still do damage, just because they don't funnel every ounce of gold into damage doesn't mean they're fighting with a wet noodle.
