This is for high Level
To get Wyvern eggs (on Valguero) just tame a Quetz and built some auto turrets on it. Then y choose a Flyer y want to use (I used a Lymantria) and put it into passive mode then Flyer to the Snow Area and watch the Wyverns falling of the sky. Then look for an Egg and when its safe take your chosen flyer and take it.
Don‘t land the quetz. After that Flyer back to the quetz (it should be in front of the Egg and land on it. Go home and welcome your baby.
I got multiple eggs with this method and Wisch y‘all good luck