Everyone rejoices when an "extinct" species is rediscovered (except possibly the person who'd been planning to build a furniture store on that spot), but does "rediscovered" mean "saved?" Unfortunately, not necessarily.
A new multinational university study came up with 351 species rediscovered in the last 122 years, but the large majority of these remain highly endangered. Species are often rediscovered in a very restricted, often disappearing, habitat. That doesn't mean rediscovery is a futile enterprise - far from it. We can't even try to conserve something that is presumed gone.
The rediscovery of the ivory-billed woodpecker (yes, I still think that was valid) led to huge efforts to conserve its habitat, but the woodpecker appears to have flown off for good. It's possible to rediscover a species when it's already too far gone.
The cahow, or Bermuda petrel, was a success story, saved by conservation measures despite having "vanished" for 300 years. On the other hand, Miss Waldron's red colobus was determined extinct, written off, and then "rediscovered" via a photograph of a dead specimen. Are there live specimens? Nobody knows.
Keep up the search!