The failure point was the deans, I am going to discharge the LiPo with a 12v car lightbulb since the LiPo is at the end of its life. My next LiPo will be EC5.
Yeah, you need genuine Deans. That being said something had to go wrong, I've never seen even generic Deans fuse together on 3S. The only time I've ever seen even generic Deans somewhat melt together was on 8S but I was still able to pull em apart.