Possible solution for "what if your session doesn't have a volcano for heating the tadpole and stuff": The old way aka Make your own yourself

I mean, yeah of course you could! It’s such an arbitrary detail after all likely you can bypass it somehow. But it still implies the lack of a Forge, and as such, a Forge-related quest to light it, which may put Hephaestus and Echidna’s being there at odds, which may lead to a whole other bunch of issues.