Ok, so basically I just found these HTTYD names trademarked by Dreamworks.
Before it was Dreamworks Dragons: Gift of The Night Fury it was:
Dreamworks Dragons: Secret of the Holiday Hatch
And before it was Dreamworks Dragons: Book of Dragons it was:
Dreamworks Dragons: Book of Dragon Secrets
Book of Dragon Secrets
To be honest these are some pretty cheesy names, that's probably why they changed it. I also found another one Dreamworks trademarked- Dreamworks Dragon Trainer, not sure what that was there for though.