I don't know that there are any frog temples on Earth C beyond what already existed, bc it's the same Earth as the Earth in the Alpha timeline, which had sburb technology so the alpha kids could play, which they did. I think the advantage of taking the same planet and putting it in the new universe is specifically so it isn't targetting for destruction. Tho, we do know its ultimate fate. Eventually, the planet will die, and become home to Calliope and Caliborn on the meteor.

The lack of any functional sburb technology on Earth C is also why Dirk and Rose had to leave the planet to search for one in their universe that did have sburb technology, which we know took at least 3 years of searching, so it seems that planets seeded with sburban technology aren't all that common.