It is not similar at all. DotA was a completely different game from Warcraft 3, Turtle WoW is just Vanilla WoW with extra content. The core gameplay is the same.

There's 3 scenarios they could follow:

1) Create a new IP with the knowledge they have from Turtle WoW, create a similar game and market it 2) Contact Blizzard, apologise and maybe be brought into the team to develop updates for Classic or Retail 3) Drop the whole thing, leave the project and disappear

Would be great to see #1, but I'm more expecting #3

Yeah, that seems like the logical next step here.