IMO and it's been my experience that only dead worms get passed in the poop. What your vet will find or may not find are the eggs in the poo from a healthy and alive parasite colony living inside of him/her.
I think most tortoises have a certain amount of parasites and most will live with them for a very long time.
Did it poop in water? right now with the rains, I've encountered small earthworms in all of my watering bowls and pools.
Just yesterday, one of my female RF took a poo in her pool, and I got a shock when I saw worms in it...Then discovered that they were small earthworms that had drowned in the pool.