Hi, for the dinosaurs and eggs to appear, you must install a Shrine, anywhere on your map. Then after 20minutes, use this items to teleport you to the egg.. cheat giveitem "Blueprint'/Game/Mods/Scorch/Scorch/Admin/PrimalItem_ScorchEggFinder.PrimalItem_ScorchEggFinder'" 1 0 false

yes that is the admin item to test if wyvern nest working on your server, it will teleport you to any nest, but it is cheat only for testing.
wyvern nest location will be completely random and spawn near any wild wyvern.

And i seem to only find Poison Eggs, no Fire or Lightning at all :<

Are the wyverns in this mod tamable? Or can i only get tamed wyvern from hatching a stolen egg?

It is adjustable if wild Wyvern can be tamed or not, check the INI Settings.

I do have the "notamingwyvern" set to false but i've been testing this mod in single player first before deciding to put it on my server. I did the "cheat dotame" command to claim myself a regular fire wyvern (not an alpha) and shortly after (about 5-10mins average) i was hit with a game crash. I was able to replicate this problem with fairly reliable frequency.

If i didn't cheat dotame a wyvern the game was able to run smooth without crashes for hours at a time without problem so that's why i thought i should ask if anyone else can confirm any problems also.

That crash caused by that Command, the same CAN ( or nothing happens ) happen with Dragon God Mod and also other Creature Mods like Annunaki, Extinction and such.

I did also have my suspicions that it could be the command aswell. I will try a natural tame and hopefully no crash :)